TCC - Light Throttle Shudder
Model Year 1983Bulletin No. 83-108
File In Group 70
Number 12
Date April '83
SUBJECT: LIGHT THROTTLE [1][2]TORQUE CONVERTER CLUTCH SHUDDER ON ALL 1982-1983 THM 125C TRANSMISSION
Since the start of production, 1982, the THM 125-C transmission has had some changes in the auxiliary valve body cover. The changes were implemented to eliminate a light throttle converter clutch shudder condition.
FIGURE 1 - CAST SLOT:
The 1982 auxiliary valve body cover originally had a cast slot in it, (Figure #1) to exhaust oil from the converter clutch regulator valve.
FIGURE 2 - ORIFICED CUP PLUG:
The auxiliary valve body cover was changed mid model year to that of having an orificed cup plug (Figure #2) in place of the cast slot. This orifice then regulated the exhaust from the converter clutch regulator valve.
FIGURE 3 - SOLID CUP PLUG:
FIGURE 4 - SOLID CASTING:
Approximately May, 1982, the auxiliary valve body cover was changed to a solid cast cover with no cup plug in it. (Figure #4).
In servicing any 1982 or 1983 THM 125-C transmission that requires replacement of the auxiliary valve body cover, order service part number is 8637811. This service package will service all past models.