4L80 Extraordinary!

GM’s race-tested-tough, street/strip overdrive automatic from Performance Automatic is the latest in a respected pedigree

- Jim Smart

GM’S 4L80E OVERDRIVE AUTOMATIC is the latest in a continuing legacy of rugged Turbo-Hydramatic transmissions from Chevrolet. Fifty years ago, the TH350 and the TH400 transmissions were a new generation of dependable three-speed automatics from GM’s Hydramatic Division. The TH350 light-duty automatic introduced in 1969 was conceived for small block V-8s while the TH400, introduced in 1964, with its higher torque capacity was engineered to handle big-block power.

At the cusp of the 1990s, GM changed the way it designated its automatic transmissions. The 700-R4 became the 4L60 that meant four forward speeds (4); and a longitudinal design (L); 60 for torque capacity, which would be a 6,000-pound vehicle weight rating. When these automatics became electronically controlled in the early 1990s, an “E” designation swiftly followed.