A/T - Harsh Park/Neutral to Drive/Reverse Engagement

Bulletin No. T 87-33
File in Group 7
Number 146
Corp. Ref. No. 707101
Date Nov. '86

SUBJECT: HARSH PARK/NEUTRAL TO DRIVE/REVERSE ENGAGEMENT AND/OR TRANSAXLE SLIPPAGE

MODELS AFFECTED: 1985-87 DE VILLE AND FLEETWOOD 1986-87 ELDORADO AND SEVILLE

Some 440-T4 transaxle may exhibit a harsh engagement from park to drive, park to reverse, neutral to drive or neutral to reverse or slippage. These conditions may be caused by a vacuum supply or response condition involving the vacuum pipe from the throttle body to the transaxle vacuum modulator.

When servicing any 440-T4 for any of the described conditions, check vacuum supply at the modulator with a vacuum gauge noting gauge reaction upon engine start up as well as response to rapid movement of the throttle. Gauge response should be immediate in both instances. If readings are below 13" or appear to respond slowly to changes in engine load and RPM, the cause could be an obstructed vacuum pipe or throttle body.

To correct this condition, remove the vacuum pipe and inspect for any obstruction. Check for crimps or damage. Reinstall or replace the pipe as required. Also check the throttle body base for plugging.

These checks should be done prior to any disassembly of the transaxle for corrective repairs for these conditions.