A/T - THM 350C No Torque Converter Clutch Engagement

TSB 87-51 (Sept)

SUBJECT: THM 350 C

PROBLEM:
No torque converter clutch engagement. Blocking the torque converter clutch valve in the upshifted position gives a torque converter clutch engagement.

POSSIBLE CAUSE:




Center direct clutch lip seal not installed, or Center direct clutch sealing ring not installed (see figures).

COMMENT:
Many THM 350C transmissions use direct clutch oil to shift the torque converter clutch valve. Removal of the direct clutch center lip seal or the center direct clutch sealing ring allows oil pressure to hold the torque converter clutch valve in the downshifted position. This prevents torque converter clutch engagement.