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.
Choosing the Right Upgrade for a Turbo 350 Transmission Pan
The GM TurboMatic 350 (TH350) is a legendary transmission, powering classic muscle cars, hot rods, and project vehicles for decades. But if you’re...
Choosing the Right Stall Converter for Your Turbo 350 and Engine Combo
The Turbo 350 (TH350) transmission is a 3-speed automatic transmission developed by General Motors in the late 1960s and widely used through the 1980s in...
Upgrading Your 4L60E Valve Body for Performance
SUMMARY: Upgrade to a rebuilt valve body for firmer shifts, improved durability, enhanced control, and better performance for towing or racing applications....
Upgrading Your 6L80 Torque Converter: Performance and Benefits
SUMMARY: The 6L80 transmission, a reliable 6-speed GM system, can develop performance issues due to its stock torque converter’s wear. Upgrading to a...
Why a 3200 Stall Converter is a Game-Changer for Your 4L60E Transmission
A 3200 RPM stall converter (or torque converter) can enhance your 4L60E transmission’s performance for high-powered applications, whether that means...
Should You Modify Your 4L60E Valve Body? Pros and Cons
Modifying your 4L60E transmission’s valve body can enhance shift performance and extend transmission life but comes with risks such as installation mishaps, a...