EXPERTEC TSB (37-4)
Publication date: 1986-11-06Reference number: 37-4
EXPERTEC TSB
TECHNICAL SERVICE BULLETIN
HARSH GEAR SHIFTING THM 440-T4 - AND/OR TRANSAXLE SLIPPAGE
Model(s): 1984-87 Oldsmobile Cutlass Ciera, Ninety-eight, Delta 88 and Toronado Models equipped with 3.8L V-6 Engines (VIN Codes B and 3) and THM 440-T4 Transaxles
Bulletin No.: Oldsmobile 37-4
Date: 12/01/1986
SERVICE INFORMATION
(Section No. 7A)
Some THM 440-T4 transaxles may exhibit harsh neutral to reverse, neutral to drive, park to reverse, park to drive, and/or transaxle slippage. These conditions may be caused by a plugged vacuum tube from the engine to the transaxle modulator.
When servicing any THM 440-T4 for this condition, remove the vacuum tube and inspect for any obstructions. Check especially for a thin coat of paint at the engine end of the pipe. Remove any foreign material so that the inner diameter of the pipe is completely open. This should be done prior to any disassembly of the transaxle for corrective repairs.