Power Transfer Unit - Viscous Coupling Failure

91chrysler09

NO.: 21-12-91

GROUP: TRANSMISSION

DATE: October 7, 1991


SUBJECT: Power Transfer Unit/ Viscous Coupling Failure 1991-1992 AWD Vehicles


NOTE: THIS BULLETIN APPLIES TO ALL WHEEL DRIVE (AWD) VEHICLES ONLY.


MODELS:

1991 - 1992 (AS) CARAVAN/GRAND CARAVAN/CARAVAN C/V
VOYAGER/GRAND VOYAGER/TOWN & COUNTRY
(BD) LASER
(B7) STEALTH
1992 (B8) COLT VISTA


DISCUSSION:

Incorrect rear tire sizes may cause some AWD vehicles to experience multiple/ repeated failures of the Power Transfer Unit and/or Viscous Coupling.

On AWD vehicles the original equipment tires have been engineered to provide optimum performance.

AWD vehicles must have the same (all four) original equipment size tires. Unequal tire sizes must not be used.

The use of oversized tires, larger than the original equipment tires, either in the front or the rear of the vehicle, can cause the front and rear driving wheels to fight (driveline wrap-up) resulting in a vehicle drive train failure.

It is recommended that tires from different manufacturers should not be mixed; the tire pressure should be maintained on all 4 tires; and the tires should be rotated as standard procedure to keep tire wear uniform.


POLICY: Information only.