Drivetrain - Rear Differential High Frequency Noise

NUMBER: 03-55-05

DATE: 04-29-05

APPLICABILITY:
2004~2005MY Impreza WRX Vehicles

SUBJECT:
Countermeasure to Eliminate Noise from the Rear Differential Area

INTRODUCTION

A countermeasure has been made to address noise coming from the rear differential area. The noise may make a high frequency "Hoo" (Harmonic) noise and is most noticeable with little to no throttle application (coasting or deceleration). The peak of the noise occurs at 63 mph (100 km/h). The noise may occur in any gear or engine speed; however it is most noticeable in 4th gear (4EAT equipped) or 5th gear (5MT equipped). Dynamic dampers were added to the rear differential member to eliminate the noise. If you encounter a customer complaint prior to the countermeasure, follow the procedure.

PRODUCTION LINE CHANGE





The countermeasure was used in production starting in April, 2004 with the VIN's shown.





PARTS INFORMATION

REPAIR PROCEDURES/INFORMATION

NOTE:
There is an identifier on the rear differential member. The earlier style is identified (marked white paint) with an "E", the newer style is identified with a "D".

Remove the rear differential member according to the procedure listed in the applicable Subaru Service Manual.





Install dynamic dampers to the new style rear differential member (pre-drilled) using self locking nuts and torque to 20 + 5 Nm (2.0 + 0.5 kgf-m, 14.5 + 4 ft-lb) (See Figure shown).

Reinstall rear differential member according to the procedure listed in the applicable Subaru Service Manual.

CLAIM REIMBURSEMENT/WARRANTY INFORMATION





For vehicles within the Basic New Car Limited Warranty period, this repair may be claimed using the table.





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