ATSG

Transmission Rebuild Tech CD-ROM

4L80E

GM Chevy

This ATSG 4L80-E CD-ROM contains general description and the procedures necessary to repair, overhaul, or service the THM 4L80-E electronic overdrive automatic transmission. The THM 4L80-E is a fully automatic rear wheel drive transmission. It provides Park, Reverse, Neutral, and four forward speeds with 4th gear being overdrive.

The shift pattern is controlled electronically with two solenoids that recieve a ground signal from the Powertrain Control Module (PCM). The PCM will vary shift points and shift feel, as it is constantly interpreting numerous electronic signals from various operational sensors located on the vehicle. The PCM also controls the Torque Converter Clutch (TCC) apply speed, apply feel, and the release electronically with a solenoid.

Line pressure and shift feel are also controlled electronically with a Pressure Control Solenoid (PCS) located on the valve body. This function is also controlled by the PCM and the numerous electronic signals from the sensors.