A/T - Forward and Reverse Engagement Shift Feel
87chevy03Number: 88-19Number: 88-19
Section: 7A
Date: May, 1987
SUBJECT: FORWARD AND REVERSE ENGAGEMENT SHIFT FEEL MODELS: 1987 LIGHT DUTY MODELS WITH THM 400 AUTOMATIC TRANSMISSIONS AND
1988 C/K MODELS WITH THM 400 AUTOMATIC TRANSMISSIONS
TRANSMISSION MODELS:
FDA, FFA, FJA, FMA, FNA, FPA, FQA FTA, FUA, FWA, FYA, FZA, LAA, LBA LCA, LDA, LFA, LHA, LJA, LKA, LMA LRA, LSA, LTA, LUA, LWA, LZA
BULLETIN COVERS:
Certain 1987 and 1988 light duty models with THM 400 transmissions (refer to list above) have new forward and direct clutch assemblies with a "dished" steel clutch plate. This new design clutch plate improves forward and reverse engagement shift feel by cushioning piston apply.
Figure No. 1 - THM 400 TRANSMISSION IDENTFICATION INFORMATION:
DATE OF CHANGE: (Figure No. 1)
July 22, 1986 (Julian Date 203) for listed 1987 THM 400 transmission models.
Figure No. 2 - FORWARD CLUTCH ASSEMBLY:
Figure No. 3 - DIRECT CLUTCH ASSEMBLY:
SERVICE ACTION: (Figures No. 2 and No. 3)
When servicing the forward and/or direct clutch, inspect the "dished" clutch plate (#612, Figure No. 2 and #624, Figure No. 3) for scoring, cracks, or flatness. Also, when servicing the direct clutch assembly, note position of the two 2.32 mm (.0915"), and three 1.97 mm (.7775"), flat steel plates (Figure No. 3, Item 622). To properly assemble
the direct clutch pack, follow the dished steel plate with: a .0915" steel plate, the second .0915" steel plate, and complete by alternating fiber and .0775" steel plates.
SERVICE PARTS INFORMATION:
Part Number Description
8625196 .054" Dished Clutch Plate
8623849 .0775" Flat Clutch Plate
8625197 .0915" Flat Clutch Plate
SERVICE NOTE:
The new forward and direct clutch assemblies cannot be used for past model service as other 1987-88 calibration changes complete by improved engagement shift feel.
SERVICE MANUAL REFERENCE:
Refer to the Forward and Direct Clutch Assembly sections of the 1987 THM 400 Unit Repair Service Manual.