This is because the TH400 was never designed to communicate with the CPU of the vehicle/The 3L80 was the last non overdrive transmission used by GM in regular production trucks and vans.
![turbo 400 transmission turbo 400 transmission](https://forunder.com/productimages/t/turbo-350-transmission.jpg)
Note that unlike all the other GM transmissions of the time there was no E at the end of the nomenclature.
![turbo 400 transmission turbo 400 transmission](https://storage.bhs.cloud.ovh.net/v1/AUTH_e7d15450bedd40b9b599e075527df3cb/fortwayne/f1967_Turbo_400_Switch_Pitch_Transmission_5c92c3cd78111.jpg)
3L80 stands for three gears, longitudinal mount (rear wheel drive), and the 80 signifies that it can handle 8000 lbs. There is no difference other than the name. In the early 90’s GM rebranded all of their transmissions, They created a standardized naming system across their product line, and changed the name of the TH400 to 3L80. It’s controlled by a vacuum module and kickdown switch Outer Case Material: Aluminum, fused with bellhousing Production: 1964 (for 65 model years) through 1990ĭifferent applications had different lengths due to different tail shafts/transfer cases. Turbo 400 TH400 Specs Manufacturer: General Motors The TH400 has appeared in Jaguars, Hummers, Ferrari’s, and many more. More than almost any transmission ever made, it has found its way into a wide variety of vehicles outside of the GM family.
![turbo 400 transmission turbo 400 transmission](https://images1.americanlisted.com/nlarge/turbo-400-transmission-for-chevy-other-bbc-parts-americanlisted_32698321.jpg)
The TH400 came in two wheel drive and four wheel drive vehicles, passenger cars and heavy duty trucks, as well as GM vehicles and those made by other manufacturers. It was introduced for the 1965 model year and made its debut in Cadillacs, and is respected for its durability and adaptability. The TH400 is an aluminum cased three speed automatic transmission that was produced by GM.