Skip to main content
search
0
All Posts By

GEARSTAR PERFORMANCE

In How To's

What Is Transmission Slipping? Signs To Look Out For

Transmission Slipping - Gearstar

Transmission slipping must be dealt with as soon as possible in order to avoid major repairs. Learn what to look out for.

The transmission is responsible for converting power from the car engine into motion for the vehicle to move. Vehicles come with a manual or automatic transmission. If you drive a car with an automatic transmission, the gears change for you while you may have to put a car with manual transmission into gear via its gear selector.

However, one of the common problems associated with transmissions is known as a slipping transmission. This article covers what transmission slipping means, its causes, signs to watch out for, how to prevent the problem, etc.

Transmission slipping: What does it mean?

Transmission slipping occurs when your vehicle unexpectedly shifts gears without responding to the current speed, often resulting in delayed acceleration or unusual noises. This can be unsettling and signals that your vehicle may need immediate attention. Ignoring transmission slipping can lead to further damage, which is why it’s crucial to address the issue as soon as you notice the symptoms.

What causes transmission slipping?

The following situations or conditions may cause your transmission to start slipping:

  • Solenoid problems
  • Worn-out gears
  • Broken or worn transmission bands
  • Burned, low, or worn-out transmission fluid
  • Clutch problems
  • Torque converter issues

Signs of transmission slipping to look out for

As with most automotive issues, the earlier you deal with it, the more successful you will be at avoiding major repairs. The longer you put off fixing your slipping transmission, the more damage you will likely compound. This will eventually cost you lots of your hard-earned money to fix.

This is why this section deals with the signs to look out for to inform you that your transmission may be slipping:

Unauthorized switching of gears

One of the signs that reveal that your transmission is slipping is that your vehicle suddenly and unexpectedly switches gears as you drive. In some cases, a change in pitch or a noise accompanies the unauthorized switching of gears.

If your car switches gear out of the blue while driving, it can be a potentially life-threatening situation. This implies that your car is unreliable and may start shaking.

When your vehicle feels sluggish

If your car is not accelerating as quickly as it should or feels somewhat sluggish, you could have a slipping transmission problem on your hands. It may also have other issues related to your transmission. This is why you should waste no time in having your vehicle checked by a professional mechanic.

Inability to change gears smoothly

Another symptom or sign of a slipping transmission is when your vehicle finds it difficult to change gears smoothly. You will hear a thud or clunk as your automobile goes down or up in gears.

When there is a delay before movement

If you experience a delay before your car starts moving, it could signify that your transmission has slipped.

As soon as the gear shift moves from ‘Park’ to ‘Drive,’ a long lag ensues before your vehicle starts moving. During this period, the car engine revs but goes nowhere.

When the clutch stops working

This is for those who drive manual transmission vehicles. When you depress the clutch pedal, and nothing happens, your clutch assembly may have been damaged, or something could be wrong with the transmission system.

When the transmission fluid leaks

When you notice a red fluid on your garage floor, coupled with some of the symptoms shared earlier, your transmission may have a problem.

This is because when there is a transmission fluid leak, it results in a slipping transmission.

Is it safe to drive your vehicle when the transmission is slipping?

Driving with a slipping transmission is unsafe because the vehicle’s performance becomes unpredictable. The risk of the transmission slipping into different gears without warning, shaking, or even causing severe mechanical damage increases the longer the issue is ignored. If you notice any of these symptoms, have your vehicle inspected by a professional immediately.

How to prevent transmission slipping

Preventing transmission slipping involves regular maintenance and mindful driving practices. Begin by routinely checking your transmission fluid to ensure it’s at the proper level and remains clean, as dirty or low fluid can lead to slipping. Address any leaks promptly, as they can cause significant damage if left unchecked. Adhering to your vehicle’s maintenance schedule for fluid changes and filter replacements is crucial for avoiding major issues. Use only the recommended transmission fluid to avoid inadequate lubrication and overheating. Additionally, avoid overloading your vehicle and monitor the cooling system to prevent overheating, a common cause of slipping.

Driving habits also play a role in prevention. Avoid rapid starts, sudden stops, and aggressive driving, which can wear out the transmission prematurely. Pay attention to any unusual sounds or shifting problems and address them immediately to prevent further damage. Regular vehicle inspections can help identify issues early. If repairs are needed, opt for high-quality OEM parts to ensure reliability. By following these preventive measures, you can extend the life of your transmission and reduce the risk of slipping. For expert advice or if you experience symptoms of transmission trouble, Gearstar is here to help. Contact us to ensure your transmission remains in optimal condition.

Fixing Transmission Slipping: DIY vs. Professional Help

While some minor transmission issues can be tackled by skilled DIY enthusiasts, such as replacing seals or adding transmission leak sealer, complex problems like a cracked torque converter should be handled by professionals. Gearstar’s team of transmission specialists has the expertise and tools to diagnose and fix slipping transmissions quickly, ensuring your vehicle is safe and reliable.

Conclusion

If your transmission is slipping, you can easily get tempted to make attempts at fixing it on your own. But if you are inexperienced or feel uncomfortable working on your transmission, the best decision you can make is to allow a transmission specialist to handle the repairs for you.

Transmission specialists have the tools and experience to detect the causes behind the slipping of the transmission. Once they diagnose the problem, they can quickly fix it within a short period, and you can get back to your day-to-day lifestyle.

In Transmission & Drivetrain

Why You Should Consider a Custom Transmission

Custom Transmission - Gearstar

A custom transmission has many benefits including top-notch performance and long term benefits. Learn more about the perks.

A vehicle transmission is one of the most crucial components of any automobile. It is responsible for moving the power from the car engine to the wheels. There are two major types of transmissions: automatic and manual transmissions you see in stick-shift vehicles. The latter requires the car driver to complete a few steps so that the vehicle operates effectively.

However, suppose you are currently in the market for a car transmission. In that case, you will be faced with two options: get a brand-new OEM transmission or get your damaged transmission professionally rebuilt.

When rebuilding your transmission, the transmission specialist takes it apart and carefully inspects every component, looking for signs of wear, tear, damage, or other issues. Every worn or damaged component will be replaced, and the entire unit cleaned thoroughly.

The transmission specialist then carefully rebuilds the transmission and reinstalls it in your drag racer, muscle car, truck, or SUV. This is a labor-intensive process that demands extraordinary attention to detail.

A brand-new OEM transmission purchased from the vehicle manufacturer seems like an excellent idea. But unless you have very deep pockets – both for the purchase, installation, and tuning of the transmission system – that option may not be for you. 

On the other hand, custom car transmissions – i.e., a car transmission that professionals have carefully rebuilt – may not look so appealing to you. Still, the benefits of going for this option are long-term.

Why You Should Opt for A Custom Transmission Over Buying a Brand-New One

Here’s why you should consider a custom car transmission over purchasing and installing a brand-new one in your muscle car or drag racer:

Superior Performance

Refurbished or used transmissions nearly always come with one form of internal damage or the other, as well as multiple Band-Aid fixes or repairs. Since they are mostly price-friendly, you may easily get tempted to purchase the refurbished or used transmission as soon as possible.

However, you may be exposing your vehicle – and yourself – to a lot of risks. There is a good chance that the used or refurbished transmission may not work seamlessly with your vehicle.

This is why it makes sense to settle for a transmission rebuild of your original car transmission. Custom transmissions guarantee superior performance and smooth operation, making your automobile sound and move like it is brand new.

Less Financial Strain

The upfront costs of rebuilding a vehicle transmission may seem un-pocket-friendly. But the truth is that the money you will save in the long run will be worth it in the end.

For instance, you won’t have to keep paying technicians a lot of money to combat problems or ongoing issues. Repairing transmissions over and over again can lower their value over time.

But this is not the case with a transmission you rebuild for your truck or car. If you eventually sell the vehicle, the custom transmission will have a warranty that enhances its value in the prospective buyer’s mind.

Eliminate Worries

The primary purpose of rebuilding a transmission is to make it run like it is brand-new, i.e., the way it came straight out of the factory. 

This means replacing every damaged or worn component – including bolts, nuts, etc. – while the still-good working parts undergo a thorough cleaning, oiling, and re-installation.

This is why you should work with a reputable mechanic shop or technician proficient in rebuilding a transmission from the ground up. You will enjoy the inner peace that comes with knowing that you won’t have to worry about buying or fixing your custom transmission.

Extended Vehicle Lifespan

A faulty transmission that is not functioning properly puts a lot of strain on other drivetrain and powertrain components. Weak transmissions also negatively affect the engine, differentials, cooling system, axles, transfer case, exhaust, suspension, and wheels.

When a pro rebuilds your transmission, it runs like a brand-new gear mechanism. This helps protect other parts of your vehicle and extends the lifespan of your truck, SUV, or car.

Retain The Transmission Originally Designed For Your Vehicle

Keeping the same transmission system originally designed for your car is the #1 benefit of sticking to a custom gear system. 

Nearly all vehicles come with a transmission that is originally designed and tuned mechanically to work with the engine and the overall drivetrain system.

Rebuilding a custom-made transmission costs far less than purchasing and installing a brand-new transmission system obtained from the vehicle manufacturer.

If you also buy a refurbished or used transmission, you will save a lot of money. However, you will also be assuming many additional risks since you may not know the condition or history of that used or refurbished transmission. There’s also an excellent chance that it may not perfectly fit your vehicle.

This may lead to incurring additional costs for repairs over time, or you may have to go through the rigors of returning it and getting another one. This will not only waste a lot of your time but will also cost you a lot of money.

This is why getting your original car transmission professionally rebuilt by specialists is an excellent, cost-efficient option.

Increase Transmission Lifespan By Replacing Parts

You can enhance the lifespan of your vehicle transmission by replacing damaged or faulty components instead of repairing them.

When you replace the parts with new ones, it gives new life to your transmission, and this helps to boost the lifespan of your transmission.

It is important to state that you should not work with technicians that quickly cut corners on the job. This will either ruin the overall performance of your transmission or significantly reduce its performance.

This can easily result in minor or extensive damages long before hitting the average life marker.

Therefore, work only with reputable technicians and ensure you take proper care of your transmission. This includes getting the transmission checked by professionals from time to time.

Conclusion

As you can see, the overall long-term benefits of opting for a custom transmission far outweigh purchasing a brand-new OEM transmission. 

Not only are you retaining the use of the original transmission custom-made for your vehicle, but you will also have a profound peace of mind, knowing that you will enjoy the use of your car for a long time.

You will also save lots of your hard-earned money over time and continue to experience the top-notch performance of your drag racer or muscle car.

The rebuilt transmission always comes with warranties, ensuring that you will get your money’s worth out of the automotive unit.

In How To's

What Is Rear End Gear Ratio and How Is It Calculated?

Rear End Gear Ratio - Gearstar

Rear end gear ratio is boiled down to lower numerical values giving better acceleration, torque, top speeds, and better fuel economy.

The first time you wade into the gears’ universe, you will encounter several terms such as gear ratio, rear end, gear systems or ‘trains,’ etc. Knowing how to calculate the rear end gear ratio to choose the right one is not a must but an advantage, and this is because you can find the gear ratio in the product description.

However, if you understand precisely how it works, your choice becomes much more calculated. Let this article serve as a guide or flashlight into this universe, and you will never get lost.

Let’s get started with the basics, shall we?

What is a Rear End Gear Ratio?

Most automobiles use gear ratios in the drive axle and the transmission to multiply power. When you multiply the two ratios, it equals the final drive ratio.

When you hear car drivers refer to numbers – such as 3.08:1, 3.73:1, or even 4.10:1 – they discuss the ring-and-pinion gears’ ratio within the rear axle. This ratio refers to the number of teeth on the ring – i.e., driven gear – divided by the number of teeth on the pinion – i.e., the drive gear.

Therefore, this implies that a ring gear with 41 teeth and a pinion with ten teeth results in 4.10:1. In other words, for every single turn of the ring gear, the pinion rotates 4.10 times. The rear end gear ratio has to do with the relationship between the pinion gear and the ring gear. 

But is there a chance that the system may incorporate more than two elements? Yes, the intermediate gears are known as ‘idlers.’ They can be used to keep – or change – the direction of rotation.

You can easily apply the gear ratio formula to every pair of wheels, but the truth is that you do not have to do so. Regardless of how many idlers there are within the train, the final gear ratio is between the ‘driver’ and the ‘driven’ wheel.

How Gears Work

The wheel was first invented before the gear came into play. Gears became functional for any of the following reasons:

  • To accurately reverse the direction of rotation
  • To decrease or increase the rotation speed
  • To synchronize the rotation and keep it that way
  • To change the rotational motion to a different axis

Although gear systems came into play as far back as four ages BC in China, many still believe that the first invention could be much older. Gear systems have developed over the centuries and are readily divided into dynasties.

The primary purpose of rear end gears is to multiply the torque the engine and transmission delivers. If you think of gears as complex mechanical levers, you won’t be far off the mark. This is because gears provide mechanical advantages that swiftly multiply torque in order to assist the engine’s power in moving the automobile.

Therefore, high gears are thought of as short mechanical levers that provide less mechanical advantage, while low gears are just like longer levers with more mechanical advantage.

Calculating the torque multiplication that your axle gears provide is quite easy. You can do this by multiplying by the gear ratio. For instance, if both the engine and transmission deliver up to 100 ft./lbs. of torque to the pinion gear and the gear ratio of the ring-and-pinion is say 4.12:1, the output torque is 412 ft./lbs. i.e. 100 x 4.12.

In the same vein, if the gear ratio is 3.04:1, the output torque will be 304 ft./lbs. As you can see, the lower 4.12:1 gears invest more power to the ground than the higher 3.04:1 gears.

Note that no changes occur in the engine’s power, though the available torque to the tires has done so.

How to Calculate Gear Ratio

The first gear that is attached to the motor shaft is known as the ‘drive’. But the ‘driven’ gear is the one that is attached to the load shaft gear.

In order to calculate the gear ratio, you need to do the following:

  1. First of all, get each part and count the number of teeth they have. Let’s say the small drive has up to 21 teeth while the driven gear has 28 teeth. Bear in mind that when experts discuss spur types, the one with more teeth is referred to as the ‘gear’ while the other one with fewer teeth is called the ‘pinion.’
  2. Divide the number of the driven gear teeth by the number of the drive gear teeth. In this example, it is 28/21 or 4:3. 

This gear ratio indicates that the smaller ‘driver’ gear must rotate or turn up to 1.3 times to get the much larger ‘driven’ to make just one complete turn.

Take note that a high numerical gear ratio is referred to as a ‘low gear.’ But a low numerical gear ratio is called a ‘high gear.’ Low gears engender fast acceleration and are highly appropriate for smaller engines.

However, high gears cause higher top speeds and better cruising and are suitable for more powerful engines.

You should heavily consider the following factors – which can affect the gear ratio – before changing the existing rear end gear ratio:

  • Tire diameter
  • Transmission type as well as individual gear ratios
  • Torque converter stall speeds (automatic), etc.

This is why it is highly essential to learn how to choose the right gear ratio for your drag racer or muscle car. 

What Do ‘Short Gear’ and ‘Tall Gear’ Mean?

The terms’ short gear’ and ‘tall gear’ can be somewhat misleading; this is why clarifying them is important.

A ‘tall gear’ gives you much better-cruising speed as well as fuel economy, while a ‘short gear’ always gives you excellent acceleration but at the cost of efficiency and cruising speed.

The Advantages That Geared Transmissions Offer

The geared transmission offers several advantages compared to other forms or types of transmission. 

First of all, a geared transmission provides incredibly high performance when efficiently transmitting motions and forces along with high reliability and extended service life.

However, what makes geared transmissions stand out from others is the astonishing accuracy of their gear ratio. This means that they can easily be utilized in precision machinery since gear ratios in geared transmissions are incredibly precise.

Moreover, unlike mechanisms – such as pulleys or chains – the size of geared transmissions is small. This makes it easy to install them in large and small machines and spaces and places that are somewhat difficult to access readily.

Finally, their maintenance is not complex in any way, and this is why geared transmissions remain one of the most prevalent systems within the automotive – and other – industries today.

Conclusion

Learning gearing lingo is important, especially if you want to know more about rear end gear ratios and how it calculated, how gear ratios affect mileage and acceleration, etc.

Rear end gear ratios can be boiled down to one statement: higher ratios – i.e., with lower numerical value – give better acceleration/torque and lower ratios yield to better fuel economy and higher top speeds.

In Transmission & Drivetrain

An Overview of The GM Turbo 350 Performance Transmission

Turbo 350 Transmission - Gearstar

Many experts consider the Turbo 350 Transmission perfect for light trucks, rally races, and entry-level sports vehicles. What makes this transmission unique is its tough parts and high performance, which give it the capacity to tackle several use cases.

Gearstar innovatively produces level two, three, and four automatic transmissions heavily backed by a full warranty.

Background

The Turbo 350 Transmission – better known as the Hydramatic 350 – is a 3-speed automatic that debuted as a joint Chevrolet/Buick project in 1969. The primary objective of this project was to replace the Super Turbine 300 2-speed Powerglide automatic.

The project also spawned several transmissions, including the 250, 250c, 350c, and 375b GM transmissions.

Identifying the GM Turbo 350 Performance Transmission

When General Motors introduced the Turbo 350 to the world, the latter was encased in a one-piece aluminum alloy housing unit. This unit measures 21.75 inches long and is comparatively light as it weighs up to 120 lbs.

It comes with a custom-made oil pan that fits in perfectly, as well as a chamfer at the rear passenger side. You can find the modulator by looking at the back of the case.

General Motors installed a lock-up torque converter in vehicles made from 1979 to 1984. This converter utilized electronic converters to make the vehicle and transmission much more fuel-efficient, especially when moving at highway speeds.

Drivers can identify the lock-up converter via an electrical plug on the driver’s side of the transmission. A plug on the left side shows you have a 350-C on your hands. Adding aftermarket conversions to these transmissions can still be worthwhile today, with up to 10 percent more fuel efficiency.

Turbo 350 Performance Transmission: Specs

General Motors introduced the Turbo 350 Transmission to conveniently replace the highly revered Powerglide 2-speed automatics in the 1960s. The following are the gear ratios the Turbo 350 features:

  • First gear: 2.52 to 1
  • Second gear: 1.52 to 1
  • Third gear: direct drive, i.e., 1.0 to 1
  • Reverse: 2.07 to 1

The Turbo 350 has no overdrive gear available.

On the contrary, the Powerglide came with the following gear ratios:

  • First: 1.82-to-1 /1.76-to-1
  • Second: 1.00-to-1

The Turbo 350 powers classic American muscle and its venerable specifications are as follows:

  • Level 2, Level 3, and Level 4 performance
  • The ability to take on as much as 700 horsepower
  • The capacity to control as much as 400 lb-ft. of torque

The power of your classic American muscle determines the horsepower you need, as much better engines will require a minimum Level 3 transmission. Due to considerable modifications, the particular transmission that handles your build with strong parts and high-quality build is always available.

The Turbo 350 shares several components – including the torque converter – with the Buick Super Turbine Powerglide and the Turbo 400. This transmission remained in production for up to 15 years until it was fully replaced in 1984 by the 700R4.

In 1980, the lockup torque converter was added but pulled four years later because of its downshifting and inconsistent acceleration.

The Turbo 350 Transmission: Construction and Size

The Turbo 350 Transmission is a single-piece transmission with a bell housing perfectly integrated into the transmission body. The entire transmission casing is made of cast aluminum.

The Turbo 350 is renowned for its short length, making it one of the lightest transmissions ever made. It takes up to 4 quarts in a pan and may require a little extra based on the torque converter in action.

When combined with a 9.5-inch converter, the overall requirement is about 10 quarts.

The additional gear the Turbo 350 came with made a no-brainer choice compared to its predecessor. This is why it is widely employed in nearly all rear-wheel vehicles – from General Motors – at the time.

Its strength, compactness, and versatility have made many vintage or classic car owners retain the transmission’s use to this day. Most vintage cars sold today also come with this powerful transmission, with minor alterations.

Turbo 350 Transmission: Benefits

The Turbo 350 empowers every driver to take their hobbies to a higher level. Only a few drivers are privileged to start their journey with the best available vehicle or the most horsepower.

If you are very new to the sport or looking to power your daily driver conveniently, the Turbo 350 is an excellent option.

The most profound benefit that the Turbo 350 brought to the table was its extra gear, one up from its predecessor. This transmission is also compact, strong, and versatile.

The Turbo 350 only had one notable weakness: the wobbling of the direct clutch drum.

Most Common Uses of the Turbo 350 Transmission

The Turbo 350 Transmission found excellent use in Pontiac Firebirds, GMC trucks, Chevrolet Camaros, Monte Carlo, and the Caprice. This transmission remarkably matches GM automobiles with small-block V-8s as well as the small Iron Duke 4-cylinder models, the block-block 396 V-8s, and V-6s.

The BOP (Buick, Oldsmobile, and Pontiac) is an offshoot version of the standard Turbo 350 that works with the Pontiac V8. You can easily differentiate one from the other by looking at the block flange. The BOP version comes with a valley, while the Chevrolet model showcases a peak.

General Motors also created several derivatives of the Turbo 350, including lock-up torque converter models with the smaller TH375, TH 250, and TH20.

Conclusion

The Turbo 350 Transmission works remarkably well with many modestly powered vehicles. It was versatile in the 1960s since it had no fixed center support and could be used in several experimental vehicles.

Even though the Turbo 350  is no longer in production, it is still employed by several classic vehicle builds. It comes with extra gear, which gives it a significant advantage over its predecessor.

The Turbo 350 Transmission is also versatile, strong, and compact. During its time, its overall strength and versatility made it popularly used in many rear-wheel automobiles from General Motors. It is still in use in several vintage or classic vehicles today.

In Maintenance

5 Symptoms of a Bad Coolant Temperature Sensor

Coolant Temperature Sensor - Gearstar

A coolant temperature sensor remains one of the most vital engine management sensors. Learn why and symptoms of a bad sensor.

The coolant temperature switch – otherwise known as the coolant temperature sensor – is primarily responsible for monitoring the engine coolant’s temperature. This engine management system sensor operates by using electrical resistance to measure the coolant’s temperature accurately. 

The signal generated is automatically transmitted to the computer so that necessary changes can be made. This includes changing the engine’s timing as well as the fuel calculations for premium performance. Most automobile engines require more fuel when they are cold but require less when fully warmed up.

If the computer detects that the engine’s temperature is too high, it will automatically scale back engine performance settings. This occurs to prevent overheating, which can damage the engine severely.

As you can see, temperature plays such a crucial role in the performance calculations of your engine. And this implies that if the coolant temperature sensor malfunctions, it may translate very quickly to engine performance hiccups.

This post discusses some of the common symptoms of a bad coolant temperature sensor. These symptoms should alert you of potential problems with your automobile and push you to have it checked out thoroughly.

Symptoms of a Bad Coolant Temperature Sensor

Overheating Engine 

If you notice that your engine overheats, the coolant temperature sensor could be the problem. At times, the coolant temperature switch may fail such that it starts transmitting hot signals permanently. 

This causes the computer to erroneously counterbalance the signal, thereby causing the engine to misfire or overheat. 

Poor Fuel Economy

Poor fuel economy is another symptom that indicates your coolant temperature sensor is malfunctioning. 

If the coolant temperature sensor malfunctions, it can transmit a false signal to the computer. And the response of the computer may unbalance the timing and fuel calculations. 

It is also common for a coolant temperature sensor to fail without warning and send permanently cold signals to the computer. The computer mistakenly assumes the engine is cold, even when it is not. 

This will cause the automobile to use up more fuel than is necessary, thereby reducing fuel economy. And this will ultimately hamper engine performance.

‘Check Engine Lights Turns On

If the ‘Check Engine’ light suddenly comes on, this could imply a hitch with the coolant temperature sensor. If the computer detects an unsavory development with the sensor’s circuit or signal, it may set off the ‘Check Engine’ light. And the light will not go off until a specialist readily addresses the issue. 

Black Smoke Emitted from the Engine

Few drivers hardly notice this crucial coolant temperature sensor symptom. But if your vehicle’s exhaust starts emitting black smoke, the coolant temperature sensor could be the culprit.

The coolant temperature sensor can fail and transmit cold signals to the computer. This action confuses the computer and stimulates it to enrich the fuel mixture unnecessarily. This can cause the fuel mixture to be vibrant such that during combustion, the fuel can’t be adequately consumed within the chamber.

This leads to the burning up of your vehicle’s exhaust pipe, thereby causing black smoke. This can be so severe that driving the vehicle in such a condition may result in environmental or excessive air pollution.

Poor Idling

A faulty sensor can cause the fuel mixture to adjust. This causes the engine to shake or vibrate when the vehicle is at low speed and can even bring about strange behaviors, power losses, etc.

Engines are highly sensitive, especially to inappropriate air-fuel mixtures at idle. This is a pointer that something is wrong with your coolant temperature sensor and must be checked out by a certified professional.

Defective Electrical Cooling Fans

Some vehicles’ coolant temperature sensors control the electric cooling fans. Most automobiles come with two different temperature sensors for the fans, engine management and dashboard gauge.

However, if your vehicle only has a single coolant temperature sensor and it becomes faulty, your electrical fans may not function at all.

Where is the Coolant Temperature Sensor Located?

Different car manufacturers and brands have distinct ways of installing the coolant temperature sensor. Its exact location also depends on its overall design.

However, the coolant temperature sensor is often located right on the cylinder head or engine block. You will find it installed conveniently on a plastic hose on the coolant’s inlet.

Some automobiles come with more than one coolant temperature sensor. This is because sometimes, these different switches can be used to send signals to the cooling fan control, dashboard, and control unit of the engine system.

If your vehicle comes with two sensors, the one that transmits signals to the control unit is often known as the coolant temperature sensor.

Diagnosing a Malfunctioning Coolant Temperature Sensor

Diagnosing should be the job of a certified technician. However, this shouldn’t stop you from examining the engine component if you suspect it is malfunctioning.

You may have to get your hands on a repair manual for the model of your vehicle. This will enable you to find the measurement values that a functioning coolant temperature switch should exhibit.

Check the service manual of your vehicle to locate your coolant temperature sensor. When you set eyes on it, disconnect the connector plugs.

If your sensor has two pins, determine the ohm measure between the pins. Then compare the value with the correct ohm-value – at a given temperature – in your repair manual. If the value does not tally, it means you need to replace the coolant temperature sensor.

If the values add up or tally, consider checking the connectors and wirings between the sensor and the engine’s control module.

You can also make use of an OBD2 Scanner to look for related trouble codes. Check the live data to see the temperature of the sensor. If the temperature is off the range, check the wirings of the sensor or replace the engine component.

Conclusion

The coolant temperature switch remains one of the most vital engine management sensors. This is because it plays a crucial role in numerous calculations that ultimately affect your engine’s performance.

This is why you shouldn’t waste any time if you suspect that the coolant temperature sensor is malfunctioning. Get a professional or experienced technician to inspect your vehicle as soon as possible.

The technician should be able to analyze or diagnose your automobile and determine if there will be a need for the replacement of the coolant temperature sensor or not.

 

In Blog Posts

Our Favorite High-Performance Transmissions

High Performance Transmissions - Gearstar

Gearstar specializes in high performance transmissions. Find out which are our favorite! Get started with Gearstar and learn what makes us different.

Are you shopping around for a GM high-performance transmission? You are welcome since this is the right place to get one. Gearstar is highly committed to engineer and builds the most satisfactory GM and Chevy high-performance transmissions that are hand-built and customized to handle as much as 1000 ft.-lbs. torque and 1200 horsepower.

Each high performance is put together by one technician – from scratch, i.e., from start to finish – using premium-quality parts on the market today. The transmissions are perfectly engineered and built to the horsepower, rear gear ratio, and torque specs of every engine it will be matched with. 

Every high-performance transmission undergoes a thorough dynamo test for up to 1000 miles to validate its excellent working condition before leaving the Gearstar facility. Each driveline component is built with the highest quality constituents, including the latest updates.

Why Refer to a Transmission as ‘High Performance’?

A high-performance transmission is usually – and much more likely – utilized for engineered and built engines for performance and speed. 

This gear mechanism used to be limited to only vehicles used exclusively for racing on the drag strip or street racing. However, over the years, there has been a lot of blurring of the line.

Many car enthusiasts these days are no longer reserving specific vehicles for those times. They are now outfitting their unique daily drivers to make them versatile enough to conform to numerous roles.

This often implies restoring and modifying their existing muscle automobiles to meet both objectives – i.e., be a reliable daily driver during the day and tear up the street or track by night or on weekends.

Matching the Engine and High-Performance Transmissions

It is vital to match your vehicle’s transmission to its engine; therefore, do not spend too much money on modifying the engine.

This is where high-performance transmission comes on the scene. To fully utilize your car engine, you must get the converter and transmission to back it up. 

High-performance transmissions provide both the speed and power that you need to get or reach peak performance, thanks to your racing engine. This includes other high-performance types of engines.

This is why you need to ensure that your high-performance transmission builder and engine builder agree or are on the same page from the beginning of the project until it is completed. 

When you are crystal-clear upfront about what you expect regarding speed, power, durability, and performance, the two builders can work together and produce the results you need in record time.

This makes Gearstar different, as you will always get the specs you request without any alteration.

The Different High-Performance Transmissions Gearstar Offers

Gearstar offers a wide range of high-performance transmissions that you can select to match your engine. Here are some of Gearstar’s lineup of GM high-performance transmissions highlighted in no particular order:

  • Ford – AOD: Level 2, 3, and 4 transmissions
  • AODE: Levels 2, 3, and 4 transmissions
  • C4: Levels 2, 3, and 4 transmissions
  • C6: Level 4 transmission
  • E4OD: Level 3 transmission
  • 4R70W: Levels 2, 3, and 4 transmissions

You will also find the following high-performance transmissions on Gearstar:

  • GM – Turbo TH350 (Level 2, 3, and 4): Stage 1 TH350 can take up to 450hp. Stage 2 holds up to 550hp. It can take from 300-350 ft./lbs. torque.
  • Turbo 400 TH400 (Level 2, 3, and 4): It can take up to 400-450hp and is rated at 450 ft./lbs. input torque.
  • 700R4 (Level 1, 2, 3, and 4): It is suitable for up to 550hp max but can do as much as 625hp. Its torque varies considerably according to its production year. But it is known to generate a maximum engine torque of about 350 ft./lbs. as well as a maximum gearbox torque of 650 ft./lbs.
  • 200-4R (Level 2, 3, and 4): It can handle up to 350-400hp on the street and 400-450hp on the track, as well as 675 ft./lbs. torque.
  • 4L60E (Level 2, 3, and 4): It is rated 450hp and 425 ft./lbs. torque.
  • 4L65E (Level 2, 3, and 4): It can handle up to 425-450hp. Built solely for Chevrolet, it has a stock torque limit of up to 380 ft./lbs. torque.
  • 4L65E C5C6 (Level 4): It can handle up to 650hp and up to 650 ft./lbs. torque.
  • 4L70E (Level 4): It can handle as much as 375hp and 350 ft./lbs. torque.
  • 4L80E (Level 2, 3, and 4): It is powered with a magnificent 800hp and generates up to 700 ft./lbs. torque.
  • 4L85E (Level 4): It is powered by a whopping 1000hp and up to 460 ft./lbs. torque.

Each Gearstar high-performance transmission is available at different price points. The power your classic vehicle has will determine the horsepower you will need, and much better engines will require a Level 3 transmission at least.

Gearstar makes every high-performance transmission that can ably handle your build with strong parts and premium-quality steel.

Every high transmission needs regular maintenance, repair, or replacement. Transmissions generally wear away every 150,000 to 200,000 miles. If your transmission has reached either limit, it is high time you changed it.

Fortunately for you, Gearstar has several new options available at affordable prices. An industry-leading warranty and thorough inspection heavily back these high-performance transmissions.

High-performance transmissions give profound peace of mind as your classic racer keeps running, and there’s zero stalling on and off the track.

High Performance Transmissions: Conclusion

As you can see, Gearstar has an excellent lineup of premium-quality, high-performance transmissions designed to match any engine of your choice. Every transmission is engineered, custom-built, and optimized – from scratch or start to finish – by a master technician, so there’s zero room for errors.

Every high-performance transmission that Gearstar features is designed and built per the torque, horsepower, and rear gear ratio specs of the particular engine it is created for.

Since every high-performance transmission is dyno-tested for an equivalent of up to 100 miles for best performance metrics, Gearstar’s products are warranted against failure for up to 36,000 miles or three years, whichever comes first right from the date of shipment.

So, what are you waiting for? Order your high-performance transmission from Gearstar today!

In Engine

The Ultimate Guide to the 4L80E Transmission

Overview of the 4L80E Transmission - Gearstar Performance

The 4L80E transmission is an automatic transmission designed by General Motors. Learn more about this legendary transmission.

The 4L80E transmission was introduced in the GM C/K Trucks line-up – to the delight of motorists – in 1991. The legendary TurboHydramatic TH400 automatic transmission was the 4L80E transmission’s immediate predecessor. It is constructed to a great extent on the 400 in strength and parts. The 4L80E also features a lock-up torque converter, an added overdrive gear, as well as state-of-the-art electronic controls. This automatic transmission has remained in production through the 2009+ model year.

In this post, you will learn more about the 4L80E transmission and its variant, i.e., the 4L85E. The latter is constructed such that it can efficiently handle heavy-duty use. Every reference to the 4L80E also applies to this variant, except where stated otherwise. 

Note that the terms’ 4L80′ and ‘4L85’ may be used without adding the suffix, ‘É.’ This is because every GM automatic is electronically controlled now and, therefore, doesn’t need differentiation. 

Let’s get to the meat of the matter.

The Development of the 4L80E Transmission

As mentioned briefly earlier, the 4L80E automatic transmission was directly developed from the TH400 transmission. The latter is a challenging and enduring transmission at GM – as well as other marques. It was practically the last hold-out of the entire old-school automatics with no overdrive or lock-up converter.

GM quickly recognized a gap revealed by the rapidly expanding success of the 4L80E/700R4 automatic transmission. Although the 700R4 was a tough transmission, it could not hold a candle to the TH400 transmission. 

And for this particular reason, GM had no choice but to start developing a pretty heavy-duty automatic overdrive.

GM relied heavily on – and used – several parts or components and designs derived from the TH400 transmission when developing the 4L80E. But the added overdrive gear gave the 4L80E an edge over its predecessor, even though it required a somewhat longer case and an extra gear set.

The rear tail housing bolt pattern was not tampered with in any way. However, its indexing bore diameter was efficiently changed. The 4L80E transmission features a large 32 spline output shaft – much like the TH400 transmission – in the numerous 2WD and 4WD applications.

The 4L80E features a die-cast aluminum case, just like most other GM automatics. However, the 4L80E never featured a removable bell housing, unlike the 4L60E automatic transmission. Instead, the 4L80E transmission showcases an integrated bellhousing with the Chevrolet 90-degree engine bolt pattern only.

In 1991, GM trucks rolled out into the market, bearing the 4L80E automatic transmission. This included the Silverado, Sierra, Suburban, Hummer H1, etc.

The 4L80E automatic transmission is by no means perfect and has its share of glitches. However, it became a huge success and continued to be enhanced throughout its production span, even with extra changes entering when required.

In 2002, the 4L85 automatic transmission entered the market. A few differences between this transmission and the 4L80E include a 5-pinion reaction gearset, a 5-pinion output gearset, etc.

GM specified a brand-new automatic transmission fluid formulation in 2006, though this development was not regarded as a transmission change. The company required this fluid formulation’s warranty in the 4L80E series. Dexron VI, another brand, highly superseded its previous transmission fluids, claiming that it has significantly improved the transmission performance as well as a more extraordinary fluid life and transmission.

The 4L80E Automatic Transmission Technology

Every 4L80E automatic transmission makes use of electronic controls, which are generally from the Powertrain Control Module. Some vehicles using this automatic transmission come with shift maps that the driver can select, based on usage, including towing, etc. 

Part of the Powertrain Control Module’s strategy includes shift stabilization, which contributes significantly to reducing hunting.

The torque converter – when applied in factories – is heavily controlled via a PWM lock-up solenoid for seamless lock-up action. Despite this, several performance aficionados always prefer to efficiently reprogram the 4L80E automatic transmission in order to run as a very simple, ON-OFF solenoid.

The H1 received a 4L80 along with its dedicated T42 transmission computer in 2004. This automatic transmission also arrived with a considerably enhanced Park/Neutral safety switch and modified transmission line pressure solenoid. Other General Motors applications are still going to follow soon.

The TCM (Transmission Control Module) refers to the highly adaptive learning computer smartly integrated within the transmission valve body. It communicates efficiently with the Engine Control Module through the onboard vehicle CAN bus network. 

This is a departure from – and a return to – preceding automotive control systems within the industry. This is because the earlier versions of electronic transmissions made use of a separate control module. This module was later integrated right into the Engine Control Module and is now known as the ‘Power Control Modules.’

But now, this high-speed CAN network permits an incredibly high rate of data sharing between these units. This occurs in order to reach a collaboration between transmission and engine functions.

Since the 4L80E automatic transmissions are – on certain occasions – used in conversion applications with the earlier non-PCM-controlled engines, GM as well as aftermarket control modules are necessary. And they are now used to control the operation or function of the transmission in these specific scenarios.

The Specifications

When you see the nomenclature of the 4L80E, it readily informs users that this is a longitudinally-mounted, 4-speed transmission designed for vehicles that weigh nothing less than 8000 lbs. The 4L80E has an RPO code – i.e. ‘MT1’ – manufactured domestically in GM’s Willow Run and Ypsilanti plants.

Here are the 4L80E ratios it features in each gear:

  • First: 2.48
  • Second: 1.48
  • Third: 1.00
  • Fourth: 075
  • Reverse 2.07

The maximum output torque of the 4L80E transmission is 885 ft. lbs. 

While the top engine input torque is 440 ft. lbs. Die-cast aluminum is the transmission’s case. And it was designed for vehicles that weigh up to 8,000 lbs. GVWR as well as with engines up to 440 ft. lbs. of torque.

However, the 4L85 was primarily designed for automobiles that weigh up to 16,500 lbs. GVWR as well as with engines up to 460 ft. lbs. of torque. This transmission has an incredible towing capacity as it was up-rated to 22,000 lbs.

The 4L80E series requires a shifter with a 7-position quadrant: P, R, N, OD, D, 2, 1. The torque converter on this automatic transmission is a fluid turbine drive, much like those found on its predecessors, e.g., the 700R4, 4L60, TH350C.

The 4L80E also comes with a lock-up pressure plate for direct, mechanically-coupled driving from the engine crank. It is 26¼ inches long and boasts a 310mm torque converter.

Applications of the Transmission

The 4L80E automatic transmission has several applications, such as:

  • Speed-sensing
  • Transfer case adaptability
  • Jeep conversions
  • Engine compatibility

Final Thoughts

By now, you already know that the 4L80E automatic transmission is intelligently designed to meet transmission challenges. This implemented automatic transmission from the legendary General Motors has an extraordinary record in conversion situations and will always leave you super-impressed.

In Engine

545RFE Transmission Specs and Schematic

545RFE Transmission - Gearstar Performance Transmissions

The 545RFE transmission is an electronically controlled unit that was great for its time until it was replaced bu the 65RFE and 66RFE. Read below for specs and more information.

The automobile universe witnessed the introduction of the 545RFE/45RFE transmission in 1999 Chrysler models. The transmission was a perfect fit for 2-wheel-drive vehicles as well as all-wheel-drive automobiles. 

The 545RFE transmission, formerly known as the 45RFE – introduced and popularly seen in the Jeep Grand Cherokee of 1999 – is highly notable for its three planetary gearsets instead of 2 planetary gearsets commonly used in a 4-speed automatic.

The 545RFE also features the following:

  • Three multiple disc holding clutches
  • Three multiple disc input clutches
  • A dual internal filter system (one filter for the fluid cooler return system and the other primary filter for transmission sump)

The 545RFE transmission, based primarily on the 45RFE automatic, was used extensively in Chrysler’s entire fleet of rear-wheel heavy-duty trucks, except for coupes and sedans.

545RFE Transmission: Specs

But back in 1998, Chrysler has introduced the 45RFE in the 1999 WJ Jeep Grand Cherokee. This transmission was paired remarkably well with the 4.7 L PowerTech V8 engine. The ’45’ refers to its torque rating, i.e., ‘5,’ while ‘4’ represents the number of forward gears. ‘RFE’ refers to the ‘rear-wheel-drive application and full electronic controls.’

But by 2001, the 545RFE transmission was produced due to a taller, extra overdrive ratio and programming changes. The new transmission had a standard axle ratio that resulted in 2000 revolutions per minute at the engine, allowing you to cruise at 110 km/h (70 miles per hour).

The 545RFE transmission found its way to several SUV and truck applications from 2001 to 2012 with Jeep Commander and Jeep Grand Cherokee models that sport higher output Hemi engines. It could also be found in several Dodge Durango models within this period.

Although the engine yield was 200 rpm less than the 45RFE, the outcome was a considerable decrease in noise and fuel consumption. Now, the 545RFE transmission had six forward speeds and one reserved for kickdowns.

The engineering of the 545RFE transmission closely resembles that of the solid Torquefiles or an up-to-date version. The 545RFE transmission had a tall 3.00:1 first gear for initial acceleration.

The reverse was designed to be equal to first gear to accommodate heavy loads easily. When the 545RFE transmission was launched, it had the broadest range of gear ratios within its class. Even the factory where the transmission was made was also brand-new.

According to experts, the 545RFE comes with 2 overdrive gears. These are relatively close to each other due to the available size. The top 0.67:1 was probably chosen since that was the largest one that could easily fit without enlarging the transmission, making it too big for the organization’s automobiles.

To be clear, the following are the 545RFE gear ratios:

First gear – 3.00:1

Second gear – 1.67:1

Second gear (Prime) – 1.50:1

Third gear – 1.00:1

Fourth gear – 0.75:1

Fifth gear – 0.67:1

Reverse – 3.00:1

The capacity of the 545RFE transmission is 10.5-11 l, while the fluid type is Dexron 3-6 or MOPAR +4.

Some models with the ‘Tow/Haul’ mode were able to make faster shifts to cut wear on the 545RFE transmission. This considerably minimized the search for gear by holding the lower gears for extended periods. It was also possible to choose lower gears when traveling downhill to boost engine braking.

The computer-controlled 545RFE transmission comes in a burnished, one-piece die-cast aluminum casing. The casing was ribbed to increase torsional rigidity. Early transmission units took up to 6.6 quarters (6.2 liters) of ATF+3 fluid, while later versions took the same amount of ATF+4 fluid.

The gear ratios were designed to provide reserve torque as the transmission was highly suitable for the large torque band of the VM 2.8 diesel, Hemi V8, 4.7 V8, and 3.7 V6.

However, in 2009, the computer was programmed so that drivers could easily select the highest gear the 545RFE transmission would shift to. This made it easier for vehicles with this transmission to tow other vehicles, climb hills, and descend without any issues.

Common Issues with the 545RFE transmission

Here are some of the common problems that the 545RFE transmission showcases:

Solenoid Pack

Since the this transmission has zero transmission bands, the 545RFE – which is electronically controlled – relies heavily on a solenoid switch pack to efficiently direct fluid to the proper clutch pack for smooth gear engagement.

If something goes wrong and the solenoid pack becomes defective, there will be no gear engagement, failure to engage overdrive, stalling of the engine seamlessly, and ‘limp mode.’

Overheating

This is another common challenge when moving parts within the transmission generate much more friction heat than the ATF can siphon away.

The primary cause of this problem involves the towing of heavy loads, multiple shifting of transmission on mountain roads, and driving in heavy stop/go traffic.

Delayed and Slipping Gear Engagement

The 545RFE transmission pump comes with a bit of a valve mechanism, which controls the fluid pressure that the torque converter transfers.

If the valve mechanism becomes faulty, you will experience significantly delayed gear engagement, stalling, torque converter/transmission overheating, reduced fuel economy, and slipping.

Harsh or Delayed 3-4 or 4-5 Shifts

Users of this transmission may experience a severe or unusual delay of 3-4 or 4-5 gear change. In such instances, it appears as if the transmission is reluctant to go into that specific gear.

This problem is linked to valve body issues in which the material used for making one of the check balls has somehow broken down so severely that fluid easily gets past and engages the underdrive clutch during the shifts.

The only way to solve this problem will be to install an upgraded #2 check ball made of a tougher material.

Four and five-speed automatic transmissions have up to 90 percent of interchangeable parts, and this makes it easy to perform repairs. The 545RFE transmission is reliable and highly durable, making serious damage a scarce thing. 

Although it was originally developed and designed to be used by heavy-duty engines, it is very compact. The use of highly active electronic control systems significantly reduced the valve body and drive shafts. 

Differences Between the 45RFE and 545RFE Transmission

The 45RFE and the 545RFE transmissions are mechanically identical. The notable difference comes down to software.

The 545RFE transmission has an electronically activated fifth gear. You will also notice that the unit control module and solenoid pack is different in both transmissions.

Conclusion

This transmission was excellent in its heydays. It was an electronically controlled unit that Chrysler produced and used extensively until it was replaced by the 65RFE and 66RFE automatic transmissions. For information on other performance transmissions and torque converters, contact us today.

In Engine

Overview of the 4L65E Transmission

4L65E Transmission - Gearstar

Gearstar – Overview of the 4L65E Transmission

The 4L65E transmission developed by General Motors for GM trucks – but adapted for the Chevrolet Corvette – is an updated version of the 4L60E. Both are automatic vehicle transmissions designed for rear-wheel-drive automobiles due to their longitudinal alignment. The 4L65E transmission was an off-shoot of the TH700R4 – ‘TH’ stands for ‘Turbo Hydramatic’– initially developed in 1982.

Even though it is a successor of the 700R4, the 4L65E transmission is an electronic automatic transmission, unlike its predecessors like the 4L60E. It comes with a 5-pinion gearset, overdrive, and a stock torque limit of up to 380 ft.-lbs. torque.

Brief History of the 4L65E Transmission

The 4L65E transmission has a history that dates back to the ’60s. At the time, General Motors launched the Turbo-Hydramatic 350 as a brand-new, highly improved automatic transmission and a worthy successor to the Powerglide.

Most GM trucks sport the TH350 as well as several rear-wheel-drive vehicles until the mid-1980s. The Turbo-Hydramatic 350 survived this long due to its sturdy build, compact size, and reliability.

Although the TH350 weighs 120 lbs. and is less than 22 inches in length, at the time, it was the transmission that packed enough punch to drive an SUV or Jeep. This transmission had no torque controller until an improved version – i.e., the TH350-C – was created.

However, General Motors eventually replaced the Turb-Hydramatic 350 transmission with the 700R4.

The 700R4 is recognized as the transmission that made the 4-speed automatic transmission incredibly popular in the market. It introduced a new feature – i.e., overdrive – for drivers in America who were somewhat more fuel-conscious I the 1980s and even beyond.

At the time, fuel prices were very high, and automobiles were still in great demand. The 700R4 transmission, which incorporated several features – such as power, durability, etc. – that made the TH350 excel in its days, allowed vehicles made by General Motors to ride smoothly and more efficiently.

The 700R4 is a non-electronic transmission that allows General Motors to meet strict emission guidelines via better fuel efficiency and access to overdrive. This helped GM customers to save a lot of money on fuel costs. Even now, the 700R4 transmission acts as a premium stock following aftermarket modifications, and this makes it easy to stick into big-block racing automobiles without electronic controls after modification.

The 4L60E eventually succeeded the 700R4 – which was once designated a 4L60 in the early 1990s – in 1997. It was GM’s #1 automatic overdrive transmission with electronic controls.

The 4L60E and 700R4 sport the same weight, length, as well as overall bellhousing. The primary difference between the two transmissions has to do with the introduction of electronic controls and an actuation system and adapted valve body to go with the new actuators and solenoids.

Throughout its lifetime, several versions of the 4L60E hit the market. And each version was only differentiated from the other via their tail housing as well as the lack – or presence – of removable bell housing. 

However, the 4L60E transmissions made after 1996 were not interchangeable and compatible with older models. This was due to a significant change in a 6-bolt tail shaft and solenoids.

Eventually, in 2001, a much stronger – and updated – version of the 4L60E transmission hit the market. This transmission was accompanied by a considerably improved input shaft and 5-pinion planetary carrier. 

The 4L65E transmission also sports a different torque controller as well as a hardened sun shell. Thanks to its planetary carrier, it also had better potential as a big block performance electronic transmission.

The 4L65E Transmission Specs

The 4L65E Transmission sports a 5-pinion planetary carrier, a 300mm input shaft, and a much better 3-4 clutch (compared to the 4L60E transmission). The following are the gear ratios of the 4L65E Transmission:

  • 1st gear: 3.06
  • 2nd gear: 1.62
  • 3rd gear: 1
  • 4th gear: 0.69

The upper limit for the 4L65E transmission is 700hp. Beyond this, it is advisable to swap this automatic transmission for a 4L85E, and the latter is much stronger but also more power-hungry and pricier.

Vehicles That Used the 4L65E transmission

Some vehicles notably featured the 4L65E transmission. Here they are in no particular order:

  • GMC Yukon Denali
  • Cadillac Escalade
  • 2005 C6 Corvette
  • Hummer H2
  • Cadillac Escalade EXT
  • 2002 Isuzu Axiom 
  • Holden One Toer 2004 Only
  • GMC Sierra Denali
  • Chevrolet Silverado SS
  • 2005-2006 Pontiac GTO (3.46:1 final drive, M32)
  • Holden Crewman 2004 Only

The 4L65E Transmission: What Sets It Apart from Other Transmissions?

It will take a little practice and mechanical know-how to easily differentiate or identify the 4L65E transmission from similar transmissions such as the 4L60E and the 4L60E/700R4. Even though the 4L65E transmission comes with a different sun shell and a much thicker input shaft, the only way to fully identify this automatic transmission is by opening it up.

Another way to pinpoint the 4L65E transmission requires in-depth knowledge of the alternate designations (M32 for the 4L60E transmission and M32 for the 4L65E transmission) – and some vital cosmetic differences – for the automatic transmissions. 

The older 4L60E transmission comes with a 4-bolt tail housing, which is different from the 4L65E transmission’s 6-bolt tail housing. Even so, the later 4L60E transmissions came with a removable bell housing as well as a 6-bolt tail housing. The performance versions of the 4L60E transmission are – on certain occasions – designate with M32.

In the end, the best way to fully identify the 4L65E transmission is to bring it to a reputable workshop. The transmission codes and designations and gauging the difference between input shafts will be checked and carried out, respectively.

However, the key differences between the 4L65E transmission and other automatic transmissions can only be visible within the transmission, i.e., when opened up.

Issues with the 4L65E transmission

Most drivers rarely have problems with the 4L65E transmission. The only major issue with this automatic transmission is the noticeably wide gear ratio between the first and second gears, i.e., 3.06:1 and 1.62:1, respectively.

This makes drivers experience a rougher transition at these speeds. However, modifying this transmission is possible, but only in some automobiles.

Conclusion

Some drivers say the 4L60E performs much better than the 4L65E transmission in some aspects. No one categorically says you can stick with only one transmission and stick with the other since choosing between these transmissions mostly depends on your budget.

You can jump to a 4L65E Transmission if you need that extra power that an additional pinion brings to the table. But if your vehicle is of a heavier build and requires more horsepower and torque, getting the 4L65E transmission would be a wise decision.

In Engine

Overview of the 2004R Transmission

2004R Transmission - Gearstar

What ultimately makes the 2004R Transmission stand out among others is its sturdy construction, and this makes it an excellent choice.

When you see the 2004R Transmission today in salvage yards or many of its spare parts in auto part stores, it can be pretty difficult to recall that it was once the belle of the transmission universe.

Even though the 2004R Transmission was less known than the other popular General Motors overdrive transmission created in the 1980s, its popularity was undeniable. And it is now more than three decades since this exceptional Transmission was launched.

Besides, if you own a classic muscle car and want to upgrade its TH-350 3-speed or Powerglide 2-speed transmission, your best move would be to opt for the 2004R Transmission. This is not only because the latter is an excellent fit for the build but also the perfect Transmission to use if you want to upgrade your classic muscle car to improve your fuel economy and more punch.

The 2004R Transmission offers a lot of features, and that is what you will learn in the following paragraphs.

Introducing: The 2004R Transmission

The 2004R refers to the 4-speed automatic Transmission created by GM for the 1981 model year. It can be used efficiently in many General Motors passenger vehicles because it was fabricated with a Chevrolet and a B-O-P bell housing bolt structure. The automatic Transmission was produced with the Buick, Oldsmobile, and Pontiac patterns.

The 2004R automatic Transmission’s bell housing, driveshaft, and mechanical speedometer enable it to be an excellent fit for vintage automobiles. Besides, the 2004R Transmission’s torque capacity and sturdy build make it a much better – and advanced – non-electric overdrive transmission for classic vehicles for General Motors.

A Brief History

The 2004R Transmission was primarily designed as a continuation of the Turbo Hydramatic line of GM transmissions. This is an automatic overdrive that you will find in cars like the Buick Grand National and Pontiac Firebird Trans-Am, as well as in high-power GM trucks.

However, for some reasons highlighted much later on here, the production of the 2004R Transmission was suddenly discontinued in 1990. And a replacement, the 700R4 Transmission, came on the scene. The 4L60, as well as the 4L60-E, are iterations of the 700R4 Transmission.

The List of Vehicles Powered by the 2004R Transmission

General Motors used the 2004R automatic transmission to power several B-body, C-body, D-body, and G-body automobiles. 

Some of the vehicles that came with the 2004R include:

  • 1981-84 Buick Electra
  • 1981-89 Cadillac Fleetwood
  • 1981-90 Buick Estate Wagon
  • 1981-89 Chevrolet Caprice
  • 1982-83 Jaguar ZR W L6 220 3.6L S S
  • 1983-87 Buick Regal
  • 1983-89 Pontiac Parisienne, etc.

Differentiating the 2004R Transmission from Others

Differentiating the 2004R automatic Transmission from the 700R4, TH350, as well as other transmissions created by General Motors, is relatively easy.

To begin with, you can quickly locate the transmission identification of the 2004R on the plate positioned on the right side of the case, pointing towards the tail shaft. This plate bears a 2- or 3-letter transmission code printed in large alphabets. 

Another way to readily identify the 2004R automatic Transmission is by counting the number of pan bolts. If it is up to 16, it is either 2004R or 700R4. A bit confusing, that’s for sure. But the size of the 2004R’s pan bolts tends to be smaller towards its end. In contrast, the 700R4 Transmission’s pan bolts maintain a perfect square all through.

It is also relatively easy to confuse the 2004R Transmission with the TH350 because they feature similar dimensions. However, the 2004R has 16 bolts on its square transmission pan, while the TH350 has 13 bolts.

The 2004R Transmission: Specs

Here is the basic information/specifications of the 2004R automatic Transmission

  • Manufacturer: General Motors (GM)
  • Production Year: From 1981 to 1990
  • Overdrive: Yes
  • Computer-controlled: No. It is controlled by a lock-up torque converter and TV cable.
  • Outer Case Material: Aluminum, expertly fused with bell housing
  • Weight: 118 pounds when devoid of the ATF or torque converter
  • Type: 3-speed automatic
  • Fluid Capacity: 11 quarts
  • Speedometer Type: Mechanical
  • Torque Converter Lock: Yes
  • Pan Bolts: 13mm heads
  • First Gear Ratio: 2.74:1
  • Second Gear Ratio: 1.57:1
  • Third Gear Ratio: 1
  • Fourth Gear Ratio: 67.10.67:1 
  • Reverse Gear Ratio: 2.07:1
  • Case Length: 27 11/16 inches

2004R vs. 7004R vs. TH350 Transmissions

If you want to, you can compare the 2004R Transmission with the 700R4 and TH350, the two other overdrive transmissions created in the 1980s. 

First of all, the 2004R transmissions share remarkable similarities with the 700R4, despite being a much weaker variant of the 2004R/700 couplet. It must be mentioned that since the 2004R Transmission was created towards the end of the vibrant production year, it is still much better than the early 700R4.

It should also be pointed out that the 2004R Transmission was not deliberately designed to equilibrize or complement the 700R4 because they accomplish similar functionalities.

However, the 2004R Transmission fits quite well within the engine bays of existing ways in many ways that the 700R4 could not. But then again, the 700R4 shares the same bell housing bolt pattern and dimension as the TH350. And this singular factor made the transmissions interchangeable in automobiles exclusively designed for the TH350 Transmission in mind.

This implies that most classic vehicles initially made to use the TH350 3-speed Transmission can swap easily to the 2004R Transmission without the need for major or significant modifications. For example, there is zero need to reduce the original driveshaft.

The 2004R Transmission: Problems

No matter how perfect a transmission system is, it will still have a few drawbacks worth mentioning.

For instance, one of the problems associated with the 2004R Transmission is its inability to go into gear when needed. The 2004R Transmission gives cause for complaint by failing to go into gear despite the proper hooking up of the linkage.

Moreover, the Transmission may fail to respond as it undergoes a test in which you try to shift it through every gear, i.e., R/D/3/2/1. Nevertheless, you can check out the fluid level by using the dipstick to see whether or not there is enough fluid within the torque converter.

Another factor you need to bear in mind is that you need to make sure the pump transmits fluid and the shifter mechanism is in excellent working condition. When using the 2004R Transmission, slipping could occur, and this may cause it to give off a signal that your vehicle needs to undergo maintenance.

Slipping is commonly evident in delayed or slow acceleration, strange smells, or even hard shifting. Ensure the fluid level is not too low and that the valve moves forwards and backward smoothly without restraint.

Conclusion

As you can see, the 2004R Transmission may have been replaced with newer or more modern transmissions. Still, it was instrumental in its heydays, especially when installation space was a significant factor that couldn’t be joked with.

This transmission was a great fit in automobiles that formerly used the TH350 Transmission, and the need for major modifications was eliminated. Moreover, many vehicles used the 2004R Transmission, including Cadillac, Buick, and Chevrolet.

But what ultimately makes this Transmission stand out among others is its sturdy construction, and this makes it an excellent choice if you decide one day to upgrade your old-school muscle vehicle.

Close Menu