A/T - 125/125C TCC Engagement in Drive, First & Reverse

TSB 87-62 (Nov)

SUBJECT: 125/125 C

PROBLEM:
TCC engagement in Drive, First Gear and Reverse

POSSIBLE CAUSE:
May have installed a torque converter drainback valve, or fitting in wrong location.

TO CHECK:
When installing these devices, remember that the THM 125 and the THM 125C transmissions pump fluid out the lower cooler line, and return to the upper cooler line.

Fluid flow must open the valve and continue past it. If the torque converter drainback valve is installed incorrectly, the result is no cooler flow.

PROBLEM:
TC stays engaged on coast-down.

CAUSE:
Normally, the cause is the TC solenoid not releasing. It may occur, only after hot operation.

CURE:
Many times the solenoid will test OK -- but replacing the solenoid corrects the condition.