REAR AXLE GRINDING NOISE (REPLACE DRUM). GMC Truck GMC Suburban

SUBJECT: REAR AXLE GRINDING NOISE (REPLACE DRUM)

MODELS: 1994 CHEVROLET AND GMC SUBURBANS AND YUKONS/BLAZERS WITH 8.5 INCH REAR AXLES

CONDITION:

SOME OWNERS MAY COMMENT ON A GRINDING NOISE EMANATING AT THE REAR OF THE VEHICLE WHILE TURNING SHARPLY TO THE LEFT OR TO THE RIGHT.

CAUSE:

AN INTERFERENCE CONDITION MAY EXIST ON THESE MODELS BETWEEN THE BRAKE DRUM AND THE BACKING PLATE. UNDER SOME CIRCUMSTANCES, THIS INTERFERENCE CONDITION MAY RESULT IN A GRINDING NOISE. THIS CONDITION WAS CORRECTED IN PRODUCTION IN NOVEMBER OF 1993.

NOTE: VEHICLES WITH AXLES MANUFACTURED AFTER JULIAN DATE 305 SHOULD NOT EXHIBIT THIS CONDITION. THE JULIAN DATE CAN BE FOUND ON THE REAR AXLE HOUSING.

CORRECTION:

FOR VEHICLES EXHIBITING THIS CONDITION, CHECK FOR AN INTERFERENCE CONDITION BETWEEN THE BACKING PLATE AND THE DRUM ON EACH REAR WHEEL. WITNESS MARKS ON THE BRAKE DRUM OR BACKING PLATE MAY INDICATE THAT AN INTERFERENCE CONDITION EXISTS. IF AN INTERFERENCE CONDITION DOES EXIST, REPLACE THE SUBJECT BRAKE DRUM FOLLOWING THE PROCEDURE BELOW.

SERVICE PROCEDURE:

1. RAISE THE VEHICLE AND SUPPORT WITH SAFETY STANDS. 2. REMOVE THE TIRE AND WHEEL ASSEMBLY. 3. REMOVE THE DRUM. 4. INSTALL A NEW DRUM. 5. REINSTALL THE WHEEL AND TIRE ASSEMBLY. TORQUE THE NUTS TO 160 N.M (120 LBS. FT.)

SERVICE PARTS INFORMATION

P/N DESCRIPTION QTY

15693462 BRAKE DRUM, YUKON/BLAZER AS REQUIRED 15693465 BRAKE DRUM, 2-WHEEL DRIVE AS REQUIRED SUBURBAN 15693466 BRAKE DRUM, 4-WHEEL DRIVE AS REQUIRED SUBURBAN

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OP DESCRIPTION LABOR TIME H0200 RIGHT DRUM R+R USE PUBLISHED H0201 LEFT DRUM R+R LABOR OPERATION H0207 BOTH DRUMS R+R TIME

FIGURES: 0

CAPTIONS: N/A

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.