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Mopar Performance Transmissions

Mopar Performance Transmissions

We offer a complete line of Mopar performance transmissions. Our product line includes NAG1 transmissions, 545RFE transmissions, and Torqueflite 727 transmissions.

We offer a complete line of Mopar performance transmissions. Our product line includes NAG1 transmissions, 545RFE transmissions, and Torqueflite 727 transmissions.

Get the most out of your powerhouse engine with one of our custom, hand-built Mopar performance transmissions. Enjoy lightning-fast shifts and minimal drivetrain power loss with Gearstar’s Mopar performance transmissions.

These transmissions are reliably capable of handling up to 1100 horsepower and 1100 ft-lbs of torque.

Unlike other Mopar performance transmissions, our transmissions are built by one master technician from start to finish.

This level of intimacy with your transmission ensures that they are mindful of your individual requirements and project needs throughout. Before a transmission leaves our facility, it is dyno tested for the equivalent of 100 miles to ensure that it is in proper working condition.

Overview of MOPAR Transmissions

MOPAR transmissions are engineered to deliver exceptional performance for Chrysler, Dodge, JEEP, and RAM vehicles.

These high-performance transmissions are built to endure the demands of high-torque and high-horsepower applications.

Available in various categories, each transmission is tailored for specific applications and horsepower ratings. With a solid reputation for reliability and performance, MOPAR transmissions are trusted by car enthusiasts and professionals alike.

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NAG1 Transmissions

The NAG1 transmission, also known as the W5A580, is a five-speed automatic gearbox engineered for performance and efficiency.

Originally developed by Mercedes-Benz and used extensively in Dodge, Chrysler, and Jeep models, this transmission has earned a reputation for its smooth shifting and durability. When properly built, the NAG1 is capable of handling substantial horsepower and torque, making it a top choice for performance applications.

At Gearstar, every NAG1 transmission is built to outperform stock units.

Our master technicians carefully disassemble, inspect, and upgrade every internal component to ensure the highest level of reliability. Custom torque converters, high-performance valve bodies, and upgraded clutch packs are just a few of the enhancements we integrate into our NAG1 builds. Whether for a daily driver or a high-powered street machine, our transmissions deliver the strength and precision necessary for peak performance.

When you choose a Gearstar NAG1 transmission, you are not just getting a rebuilt unit—you are receiving a high-performance transmission built to exceed expectations.

545RFE Transmissions

The 545RFE transmission is a five-speed automatic gearbox designed for durability and efficiency.

Originally introduced by Chrysler, it has been widely used in Dodge Ram trucks, Jeep Grand Cherokees, and other high-performance Mopar vehicles. Known for its rugged construction and adaptive shifting technology, the 545RFE offers smooth power delivery while handling heavy loads with ease.

At Gearstar, we take the factory 545RFE and refine it into a transmission capable of handling extreme conditions and high-performance applications.

Our expert technicians meticulously upgrade each unit, replacing stock components with high-strength materials designed to withstand increased torque and horsepower. Enhanced clutch packs, custom torque converters, and recalibrated valve bodies ensure that our 545RFE transmissions provide superior shift quality, responsiveness, and longevity.

Whether you need a transmission that can handle the demands of towing, off-roading, or high-horsepower performance, our custom-built 545RFE is engineered to exceed expectations. When it comes to reliability and power, Gearstar delivers a transmission you can trust.

Torqueflite 727 Transmissions

The TorqueFlite 727 transmission is a true icon in the automotive world.

First introduced in the late 1950s by Chrysler, the 727 has earned a legendary status for its robust construction and ability to handle high-torque applications. It became the go-to transmission for muscle cars, performance vehicles, and heavy-duty trucks, thanks to its durability and smooth shifting. Even today, the 727 continues to be revered by enthusiasts who demand a transmission that delivers unmatched strength and reliability.

At Gearstar, we take the classic TorqueFlite 727 and elevate it to new heights of performance.

Our custom-built 727 transmissions are designed to handle the rigors of modern-day performance, whether you’re building a high-powered street machine or a race-ready vehicle. Every unit is meticulously assembled with upgraded internals, including high-strength clutches, precision-machined valve bodies, and custom torque converters, ensuring that it can handle the increased power and torque that modern engines produce.

Whether your vehicle is a classic muscle car, a street rod, or a heavy-duty workhorse, Gearstar’s TorqueFlite 727 is built to deliver the performance you demand, mile after mile, year after year.

Ford Transmissions

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Mopar Transmissions

High Performance Automatic Transmissions & Converters | Gearstar Performance

Converters

Torque Converter Technology

Torque converter technology is a cornerstone of MOPAR transmissions, significantly enhancing their performance and efficiency.

A torque converter is a fluid-filled coupling that seamlessly connects and disconnects the engine from the transmission, ensuring smooth and effortless shifting. Unlike traditional mechanical couplings, torque converters utilize fluid pressure to transmit power, which reduces wear and tear on both the transmission and the engine.

MOPAR transmissions incorporate advanced torque converter technology, including the Guardian torque converter, designed for heavy-duty applications to provide superior performance and reliability.

Transmission Maintenance and Troubleshooting

Maintaining your MOPAR transmission is crucial for ensuring its longevity and optimal performance.

Regular maintenance tasks, such as changing the transmission fluid and replacing filters, can prevent premature wear and tear. Additionally, troubleshooting common issues like slipping or hesitation can help identify and resolve problems before they escalate into major repairs.

By adhering to a dedicated maintenance schedule and utilizing a comprehensive troubleshooting guide, MOPAR transmission owners can keep their vehicles running smoothly and efficiently.

For additional assistance with your Mopar transmission, visit Gearstar’s dedicated Support Page here.

This page provides valuable resources to help you with everything from installation tips to troubleshooting.

Whether you’re seeking technical guidance or need help with warranty information, Gearstar’s support team is ready to assist you. Make sure to explore the FAQs and reach out for personalized support if needed.

MOPAR Transmission Applications

MOPAR transmissions are versatile and designed to meet the demands of various applications, from diesel-powered vehicles to high-performance racing.

Whether you’re building a high-performance car or seeking a reliable transmission for your daily driver, MOPAR transmissions are renowned for their exceptional performance and reliability, making them a go-to choice for automotive enthusiasts.

Transmission Accessories and Support

Beyond their high-performance transmissions, Gearstar’s MOPAR performance transmissions offer a comprehensive range of transmission accessories and support products.

From torque converters and transmission filters to gear sets and transmission pans, our MOPAR transmissions provide everything needed to keep your transmission in top condition.

With a dedicated team of engineers and technicians, Gearstar also offers expert support and service to help you maximize the performance of your transmission. Whether you’re a professional mechanic or a DIY enthusiast, Gearstar has the resources and expertise to support your transmission needs.

Getting an Estimate for Your Mopar High Performance Transmission

If you are considering a transmission replacement but are unsure which option best suits your Mopar vehicle, you can request an estimate today.

Our team of experts will guide you through the selection process, taking into account your specific vehicle model, performance goals, and budget. Whether you are looking for a stock rebuild or a fully custom high-performance transmission, we will provide you with a detailed and transparent estimate tailored to your needs.

At Gearstar, we believe in helping our customers make informed decisions by offering personalized advice and recommendations for the best transmission solution. Contact us today to get started and experience the difference of working with a trusted leader in Mopar transmissions.