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Built to Hold

Build guides, transmission tech, and install notes from the Gearstar shop floor. Every unit we ship is assembled by one builder, matched to your combo, and dyno-tested before it goes out the door. This is where we show the work: what holds, what grenades, and how to spec it right the first time.

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

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

GEARSTAR PERFORMANCE 6 minute read

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...

An Overview of The GM Turbo 350 Performance Transmission

An Overview of The GM Turbo 350 Performance Transmission

GEARSTAR PERFORMANCE 5 minute read

Many experts consider the Turbo 350 Transmission perfect for light trucks, rally races, and entry-level sports vehicles. What makes this transmission...

Our Favorite High-Performance Transmissions

Our Favorite High-Performance Transmissions

GEARSTAR PERFORMANCE 5 minute read

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

5 Symptoms of a Bad Coolant Temperature Sensor

5 Symptoms of a Bad Coolant Temperature Sensor

GEARSTAR PERFORMANCE 6 minute read

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

545RFE Transmission Specs and Schematic

545RFE Transmission Specs and Schematic

GEARSTAR PERFORMANCE 6 minute read

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...

The Ultimate Guide to the 4L80E Transmission

The Ultimate Guide to the 4L80E Transmission

GEARSTAR PERFORMANCE 6 minute read

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

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