The 3-speed Turbo-Hydramatic 125 was introduced in 1980 and produced through 2002. It carried over some parts from the light-duty Turbo-Hydramatic 200 and 350, but was generally a new design.
The 125 was renamed 3T40 later, following GM's new naming convention. The 4T40-E replaced it starting in 1995.
Applications:
- 1982–1996 A-body
- 1980–1985 X-body
- 1982–2002 J-body
- 1990-1993 W-body
- 1987–1996 L body
- 1990–1995 U-body vans (with LG6 engine)
- 1984-1988 Pontiac Fiero
Read more about this topic: Turbo-Hydramatic 125