727 Transmission

The TorqueFlite 727 is one of the most iconic automatic transmissions ever produced by Chrysler. Originally introduced in the late 1950s, the 727 quickly became known for its strength, smooth shifting, and ability to handle serious power.

This transmission was used across a wide range of performance vehicles, trucks, and muscle cars throughout the 1960s, 70s, and beyond. Its aluminum case construction reduced weight by around 60 pounds compared to earlier cast-iron designs, improving both performance and handling. Adding modifications or upgraded components, such as oil grooves or performance parts, can further enhance the 727 transmission's lubrication, durability, or overall functionality.

At Gearstar, we specialize in taking this legendary 727 transmission and refining it for modern performance needs. Every 727 we build is crafted by a single master technician, using the highest-quality components and performance upgrades to ensure unmatched reliability and precision.

Basics About the 727 Transmission

The 727 transmission is a three-speed automatic designed for longitudinal engine configurations. Its durable design and smooth operation have made it a favorite for decades among muscle car enthusiasts and heavy-duty vehicle owners alike.

The transmission’s three forward gears and one reverse gear are optimized for both acceleration and efficiency. With its proven internal design and dependable torque handling, the TorqueFlite 727 remains one of the most respected transmissions in automotive history.

At Gearstar, our custom-built 727 transmissions are engineered to handle today’s high-horsepower engines. Each build includes upgraded internals, precision-machined valve bodies, high-strength clutches, and custom torque converters designed to manage extreme torque and performance demands. We increase the number of clutch plates and friction discs in our upgraded builds, which significantly enhances durability and overall performance.

Key Features of the 727 Transmission

Legendary Strength and Durability

The TorqueFlite 727 is famous for its toughness. Its robust aluminum case provides excellent heat dissipation and reduced weight, while its strong internal components deliver long-term durability under demanding conditions.

Note: Proper band overlap adjustment is critical for maximizing the 727's durability and preventing premature wear of internal components.

Smooth Shifting and Performance

The 727 is celebrated for its smooth, consistent shifting thanks to its series of planetary gear sets that manage the transition between first gear, second gear, and third gear, allowing for efficient acceleration and cruising. The valve body acts as the control center, directing hydraulic pressure to engage the correct gear at the right time.

Drivers can select different gears or driving modes using the shift mechanism, allowing for precise control over performance. Carefully calibrated gear ratios deliver strong off-the-line performance and smooth cruising at higher speeds.

Superior Lubrication and Cooling

Lubrication is critical to longevity, and the 727 excels in this area. It features a large capacity oil pan, which, along with the oil filter, plays a crucial role in maintaining clean, cool fluid, ensuring proper lubrication, and extending the life of internal parts. This design helps prevent overheating and wear, even in high-performance environments.

Advantages of the TorqueFlite 727 Transmission

Exceptional Power Handling

A stock 727 transmission can typically manage up to 450–500 horsepower. However, a Gearstar-built 727, featuring upgraded internals and performance tuning, can reliably handle up to 600 horsepower or more, depending on your specific build.

Reliability Under Pressure

The 727 is renowned for its long service life. When properly maintained with regular fluid changes and inspections, it provides years of dependable service. Gearstar’s precision-built units are also dyno-tested to verify perfect performance before shipping.

Perfect Fit for Muscle Cars and Performance Builds

The TorqueFlite 727’s design makes it a strong match for Mopar engines, muscle cars, street rods, and high-performance classics. In certain vehicle models, especially in 1964 and 1965, the 727 transmission was paired with a floor-mounted shift lever, replacing earlier push-button controls. Whether you’re building a drag car or a reliable daily driver, the 727 delivers consistent power and durability.

Upgradeable and Customizable

Like other Gearstar transmissions, the 727 can be fully customized to suit your build. Options include custom torque converters, improved valve bodies, and lubrication upgrades, all tailored for your specific horsepower and driving style.

Frequently Asked Questions About the 727 Transmission

How much horsepower can a 727 handle?

A well-maintained factory 727 can typically handle around 450–500 HP. With Gearstar’s performance upgrades, including reinforced internals and improved lubrication, our custom 727 builds can safely handle up to 600+ HP, making them ideal for modern, high-output engines.

How many gears does a 727 transmission have?

The 727 transmission features three forward gears and one reverse gear. Its gear ratios are:

• 1st Gear: 2.45:1

• 2nd Gear: 1.45:1

• 3rd Gear: 1.00:1

• Reverse: 2.20:1

This setup provides a perfect balance between low-end torque and highway efficiency.

Will a 5.7 Hemi bolt up to a 727 transmission?

Yes, a 5.7L Hemi can bolt up to a 727 transmission, but it requires an adapter kit to properly align the bellhousing and torque converter. Once installed, this combination offers excellent strength, torque handling, and reliability, making it a popular Mopar swap option.

What’s the difference between a 727 and a 904 transmission?

The main difference between the 727 and 904 transmissions lies in their size and strength. The TorqueFlite 727 is the larger, heavier-duty version designed to handle more torque and horsepower. The TorqueFlite 904, on the other hand, is a lighter and more compact transmission originally designed for smaller engines and everyday driving applications.

Buy a Custom-Built 727 Transmission from Gearstar Performance Transmissions

The 727 transmission continues to be one of the most dependable and performance-ready Mopar transmissions ever built. Whether you’re restoring a classic Mopar, upgrading your street machine, or building a track-ready vehicle, Gearstar’s custom-built 727 transmissions are engineered to deliver maximum strength and reliability.

Every Gearstar transmission is built start-to-finish by one master technician and dyno-tested under load before shipping, ensuring the performance, precision, and durability you expect from the best.

If you’re ready to upgrade to a custom-built 727 transmission, contact us today or explore our selection of performance transmissions to find the perfect fit for your build.