A/T - 125/125C Input Drum Contacting Center Support

TSB 87-27 (Apr)

SUBJECT: 125/125C

PROBLEM:




The back of the input drum is contacting the center support, (low-reverse clutch housing), causing metal contamination. See Figure 1.

CAUSE:
A step has worn into the center spline of the reaction internal gear, causing the entire gear train to have excessive end play.

SOLUTION:




Instead of replacing the reaction internal gear, machine .060 from the rear surface of it ("A" in Figure 2). Install snap ring, part number 8621331 at point "B" in Figure 2. (note: no previous snap ring)

This snap ring is approximately .060 - .062 in thickness, and replaces the machined area of the reaction internal gear. The gear train will push against the snap ring, not the center tooth area of the reaction internal gear, as it did previously.

The input drum and the center support may not need replacement. Remove any loose metal from those parts with a wire wheel to prevent metal contamination.

Note
Part number 8621331 is the snap ring used on the THM 200 output shaft, behind the rear internal gear on some models. Make it a practice always to check for a step worn on the center spline of the reaction internal gear. The input drum may not be contacting the center support; if very close, a correction is necessary.