A/T - THM 125C Harsh 1-2 Shift
87chevy20Number: 87-231
Section: 7A
Date: Oct., 1987
Subject: HARSH 1-2 SHIFT THM 125C
Model and Year: 1987 CAVALIER, CELEBRITY, CORSICA, BERETTA WITH THM 125C TRANSAXLE
TO: ALL CHEVROLET DEALERS
FIGURE 1 - THM 125/125C TRANSAXLE IDENTIFICATION INFORMATION:
Vehicles equipped with a THM 125C built between the dates of April 13, 1987 through April 21, 1987 (Julian Dates 103-112 Figure 1), may have a rolled or misassembled 1-2 accumulator piston seal, resulting in a possible harsh 1-2 shift. These transaxles have a new design accumulator piston (flat inner surface) and a soft synthetic rubber 1-2 accumulator piston seal that may be inadvertently misassembled.
FIGURE 2 - ACCUMULATOR PISTON SEALS:
If this condition is experienced in a transaxle built between these date codes examine the 1-2 accumulator piston and seal for damage or misassemble. If necessary, replace the piston and seal with the original design accumulator piston (raised rib) and P.T.F.E. seal. These parts are not interchangeable (refer to Figure 2).
SERVICE PARTS INFORMATION:
8631657 1-2 Accumulator Piston
8631895 1-2 Accumulator Piston Oil Seal Ring