T1000 L4-111 1.8L DSL (1983)
Clutch: Customer Interest
A/T - Slipping or No Upshift/Burned Second Clutch
Number
87-7-19
Date
4/87
Subject:
SLIPPING OR NO UPSHIFT - BURNED SECOND CLUTCH
1981-87 T1000 MODELS EQUIPPED WITH THM 180/180C TRANSMISSIONS (MD3/MD2)
Figure 1 - THM 180/180C Transmission Identification Information
Figure 2
TRANSMISSION MODELS:
ND, NS, VN, ST, VQ, TN, TP, PR, UR
BULLETIN COVERS:
A 1981 through 1987 THM 180/180C transmission (refer to Figure 1) may exhibit a slipping or no upshift condition due to a burned second clutch. The
burned second clutch may be due to distortion of the valve body spacer plate which results in loss of second clutch apply pressure. The valve body
spacer plate may become distorted when the vacuum pipe fitting (refer to Figure 2) becomes blocked by carbon at the engine intake manifold. As the
fitting is blocked off, the second clutch check ball vibrates back and forth against the spacer plate causing the distortion..
SERVICE ACTION:
To service a THM 180/180C transmission for a slipping or no upshift condition, inspect and replace as necessary, the second clutch plates, third clutch
plates, the valve body spacer plate and gaskets. Check the vacuum modulator, using J 24466 Modulator Checking Tool; and clean the vacuum pipe
fitting assembly.
