Rear Axle - Whine
BULLETIN NUMBER: 93-4B-54SECTION: 4B
NUMBER: 2
CORPORATE REFERENCE NUMBER: 164202R
DATE: March 1993
SUBJECT:
REAR AXLE WHINE NOISE (REPLACE AXLE SHAFT)
MODELS:
1990-93 M/L VANS
THIS BULLETIN CANCELS AND REPLACES GMC TRUCK SERVICE BULLETIN
91-4B-171 DATED DECEMBER 1991 TO UPDATE APPLICABLE MODEL YEARS.
Owners of some 1990-1993 M/L vans may comment on rear axle whine. The whine may be caused by axles which were manufactured with grind chatter marks on the bearing ride surfaces of the rear axle shafts. The grind chatter will cause a "Whine" noise which is noticeable during both drive and coast over the entire speed range. The bearing ride diameter is correct in all cases. The grind chatter marks are visible as longitudinal lines in the bearing ride surface.
SERVICE PROCEDURE
Grind chatter can only be recognized in the bearing ride area by doing the following:
1. Clean/polish bearing ride area without introducing scratches.
2. Hold axle shaft horizontally under direct light.
3. Sight along horizontal center line of the shaft.
4. Chatter marks will appear as a systematic pattern of imperfections going all the way around the circumference of the bearing ride surface.
5. If an axle fits the above criteria, replace the suspect axle shaft (P/N 26015257 LH or 26015258 RH) using the procedures described in the M/L Service Manual section 4B1.
SERVICE PARTS INFORMATION
Part Number Description
26015257 Axle Shaft (LH)
26015258 Axle Shaft (RH)
Parts are currently available from GMSPO.
WARRANTY INFORMATION
For vehicles repaired under warranty use:
Labor Oper. Description Labor Time
F1530 Axle Shaft Repl. (RH) 0.7 hrs.
F1531 Axle Shaft Repl. (LH) 0.7 hrs.
F1537 Axle Shaft Repl, (both) 0.8 hrs.