3L80/3L80HD (400/475) Automatic Transmission

Fig. 1 Cross-Sectional View Of Turbo Hydra-Matic 3L80 & 3L80HD (400 & 475) Automatic Transmission:

This transmission, Fig. 1, is a fully automatic unit consisting primarily of a three element hydraulic torque converter and a compound planetary gear set. Three multiple disc clutches, two one-way clutches, and two bands provide the friction elements required to obtain the desired functions of the planetary gear set. The two one-way clutches, each consist of two roller clutches.
The torque converter, the multiple disc clutches and the one-way clutches couple the engine to the planetary gears through oil pressure, providing three forward speeds and reverse. The torque converter, when required, supplements the gears by multiplying engine torque.