GM Service Manual Online
For 1990-2009 cars only

No Third Gear -- D4

Checks

Cause

Direct Clutch Components

  • Seal (620, 621, 622)

Leaking

  • Ball Check

Leaking

  • Piston (619)

Cracked or jammed

  • Housing (623)

Cracked

  • Reaction Plates (618)

Worn splines

  • Friction Plates (611)

Worn splines or worn friction

  • Spring Assembly (607)

Jammed

  • Center Support Seals (639)

The seals are leaking at the center support hub

  • Center Support (640)

The support is broken or leaking at the case

  • Center Support Bolt (25)
    • Loose or broken
    • Blocked hole
  • 2-3 Solenoid (311)
    • Stuck Off
    • Pinched wire
    • O-ring failure
    • No voltage to the solenoid
  • VCM/PCM

No signal to the solenoid

  • 2-3 Shift Valve (312)

Stuck

  • Quad Driver Module

Failed

Check the VCM/PCM for current DTCs