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.
Is a 4L65E Stronger Than a 4L60E?
Wondering if the 4L65E transmission is stronger than the 4L60E? In short, yes. The 4L65E is an upgraded, heavy-duty 4L60E introduced initially for trucks, and...
How Much Horsepower Can a 700R4 Transmission Handle?
A stock 700R4 in good condition handles about 350 lb-ft of torque and roughly 300 to 350 horsepower. GM rated it to move a vehicle up to a 6,000 pound...
Why the GM 4L75E Transmission is a Top Choice for Performance Enthusiasts
The GM 4L75E transmission is a high-performance automatic transmission ideal even today for car enthusiasts seeking durability and power. Enhanced to...
TH400 vs 4L80E vs 6L80E: Which GM Heavy Duty Automatic Belongs Behind Your Build?
All three of these will hold serious power. The question is not which one is strongest, it is which one matches the car you are actually building. If you...
How Do I Know if My Transmission Solenoid is Bad?
A bad transmission solenoid causes delayed or erratic shifting, slipping, harsh shifts, or a flat refusal to shift at all. Other warning signs are...
Are 4L60E and 4L65E Interchangeable? Understanding the Differences and Compatibility
Physically, yes. The 4L60E and 4L65E share the same case, the same bellhousing bolt pattern, the same mount location, the same tailhousing, the same cooler line...