Driveline Vacuum Motor - Revision
NO.: 03-03-93GROUP: Rear Axle
DATE: Jun. 04, 1993
SUBJECT:
Rear Drive Line Module Vacuum Motor Revision
MODELS:
1991-1993 (AS) Caravan/Grand Caravan
Voyager/Grand Voyager/Town & Country
NOTE:
THIS BULLETIN APPLIES TO ALL WHEEL DRIVE VEHICLES.
DISCUSSION:
A new vacuum motor has been released which incorporates a larger shaft to bushing seal and a felt wiper to prevent contaminants from reaching the seal. The motor return spring is now incorporated internally eliminating the need for the external spring. These changes result in improved motor sealing and reduce the spring stress (see illustrations). The revised vacuum motor is P/N 4641566. When using this revised vacuum motor, the external spring is to be discarded.
Failure of the vacuum motor seal can cause the transfer of automatic transmission fluid from the overrunning clutch housing into the vacuum reservoir. This can result in a deterioration of the operation of the drive line module. The white plastic vacuum reservoir located on the torque tube can be checked for the presence of transmission oil by holding a shop light behind it.
Drain any transmission oil from the vacuum reservoir. If the vacuum hoses are soft/mushy they should be replaced. Any transmission fluid lost from the overrunning clutch case should be replenished to the correct level.
POLICY: Information Only