GM Service Manual Online
For 1990-2009 cars only

Component

Inspect

Valve Body Assembly

    • 1-2 shift valve train stuck
    • Spacer plate or gaskets are incorrect, incorrectly assembled or damaged
    • 1-2 accumulator valve stuck
    • Face not flat

2-4 Servo Assembly

    • Apply pin too long or too short
    • 2nd servo apply piston seal missing, cut or damaged
    • Restricted or missing oil passages
    • Servo bore in case damaged

2nd Accumulator

    • Porosity in 1-2 accumulator housing or piston
    • Piston seal or groove damaged
    • Nicks or burrs in 1-2 accumulator housing
    • Missing or restricted oil passage

2-4 Band

Worn or incorrectly positioned

Oil Pump Assembly or Case

Faces not flat