GM Service Manual Online
For 1990-2009 cars only

Condition

Possible Cause

Slipping or rough 1-2 Upshift

    • Low fluid
    • TV cable out of adjustment, binding or damaged
    • Throttle valve binding or sticking
    • 1-2 shift valve binding or sticking
    • Primary regulator valve binding or sticking
    • Intermediate servo seals cut or damaged
    • Intermediate servo piston binding or sticking
    • Intermediate servo piston rod not engaged
    • 2nd brake band worn or out of adjustment
    • Torque converter internal damaged
    • Forward clutch discs worn
    • Forward clutch piston or seal leaking or damaged
    • Forward clutch input shaft O-rings cut or damaged
    • Incorrect line pressure