Torque Converter Clutch - Light Throttle Shudder

Number 83-T-31 Section 7 Date 05/83
Subject: LIGHT THROTTLE [1][2]TORQUE CONVERTER CLUTCH SHUDDER - ALL 1982 AND 1983 THM 125C MODELS
Since the start of production, 1982, the THM 125C transmission has had some changes in the auxiliary valve body cover. The changes were implemented to eliminate a light throttle converter clutch shudder condition.

VIEW A - CAST SLOT:

The 1982 auxiliary valve body cover originally had a cast slot in it (see illustration, View A) to exhaust oil from the converter clutch regulator valve

VIEW B - ORIFICED CUP PLUG:

The auxiliary valve body cover was changed mid-model year to that of having an orificed cup plug (see illustration, View B) in place of the cast slot. This orifice then regulated the exhaust from the converter clutch regulator valve.

VIEW C - SOLID CUP PLUG:

Approximately May 1982, the auxiliary valve body cover was changed to omit the orifice in the cup plug (see illustration, View C).

VIEW D - SOLID CASTING:

The current production auxiliary valve body cover was changed to a solid cast cover with no cup plug in it (see illustration, View D)..
In servicing any 1982 or 1983 THM 125C transmission, that necessitates the replacement of the auxiliary valve body cover, order service part number 8637811. This service package will service all past models.