The 6T30/40/45/50 transmission utilizes a line pressure control system during upshifts to compensate for the normal wear of transmission components. As the apply components within the transmission wear or change over time, shift time (the time required to apply a clutch) increase or decreases. In order to compensate for these changes, the transmission control module (TCM) adjusts the pressure commands to the various PC solenoids, to maintain the originally calibrated shift timing. The automatic adjusting process is referred to as ?daptive learning?and it is used to ensure consistent shift feel plus increase transmission durability. The TCM monitors the A/T input speed sensor (ISS) and the A/T output speed sensor (OSS) during commanded shifts to determine if a shift is occurring too fast (harsh) or too slow (soft) and adjusts the corresponding pressure control (PC) solenoid signal to maintain the set shift feel.
The purpose of the adapt function is to automatically compensate the shift quality for the various vehicle shift control systems. The adapt function is a continuous process that will help to maintain optimal shift quality throughout the life of the vehicle.
Ignition Transmission Lock Check
Transmission Assemble (Gen 1)Disarming the System
To disarm the system, either unlock the doors using the RKE transmitter, or start
the vehicle with a recognized transmitter in the vehicle.
To avoid setting off the alarm by accident:
Press on the RKE transmitter.
Start the vehicle.
To avoid setting off the alarm by accident:
Lock t ...
OnStar Overview
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect
to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic
Services.
The OnStar system status light is next to the OnStar buttons. If the status light
is:
Solid Green: System is ...
Steering Gear Boot Replacement
Special Tools
CH-804 Tensioner
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
Remove the steering linkage outer tie rod. Refer to Steering Linkage
Outer Tie Rod Rep ...