The 4L60E and 4L80E are two of General Motors’ most discussed automatic transmissions, and the choice between them shapes how a truck, SUV, or LS swap behaves on the street and under heavy load. Both ...

The 4L60E is the latest in a long line of durable, high-function GM overdrive automatics that have come our way since the 1960s. The TH350 three-speed automatic had long been a mainstay with Chevy ...

Poor reliability is a car problem that isn't as prevalent as it used to be. Automatic transmissions were among the worst offenders, with some going from smoothly shifting between gears while ...

Using our normal bull-in-a-china-shop approach, we were able to get the wrong transmission behind an engine that it wasn’t designed for. Of course, we didn’t know that at the time, and built the ...

With their debut in the 1990s, GM's 4L60E and 4L80E transmissions reveal some of their differences –- and similarities –- right in their names. The "4" and "L" respectively refer to the number of ...