REAR AXLE CLEANING/LUBRICATION INFORMATIONAL PROCEDURES

SUBJECT: INFORMATION ON REAR AXLE CLEANING/LUBRICATION PROCEDURES

VEHICLES AFFECTED: 1992-93 C5H, C6H AND C7H MODELS WITH EATON REAR AXLES

Synthetic lubricant is standard for 1992-93 Eaton rear axles. Synthetic gear lubricants result in increased rear axle life and reduced maintenance.

When changing the lubricant or performing service work on the rear axle, wipe the interior of the bowl clean with a lint-free rag and an acceptable solvent such as brake cleaner or equivalent. It is not necessary to remove and clean wheel equipment due to negligible lube transfer between the sump and hubs. After cleaning the rear axle, refill with lubricant using the following procedures for hubs without filler holes.

IMPORTANT: AFTER REMOVING THE HUBS, THE HUBS' LUBE CAVITIES ARE EMPTY. BEARINGS AND SEALS MUST BE MANUALLY SUPPLIED WITH ADEQUATE LUBRICANT OR THEY WILL BE SEVERELY DAMAGED.

SERVICE PROCEDURE:

1. Block the wheels and set the park brake to prevent the vehicle from rolling.

2. Fill the axle with synthetic lube P/N 12345841 through the axle housing filler hole.

3. Jack up the left side of the axle. Maintain this position for one minute so the lube can flow into the wheel ends at the right side.

CAUTION:

BE SURE FRONT WHEELS ARE SECURELY BLOCKED. DRIVELINE MOUNTED PARKING BRAKES WILL NOT HOLD A VEHICLE WITH THE REAR WHEELS OFF THE GROUND.

4. Jack up the right side of the axle. Maintain this position for one minute so the lube can flow into the wheel ends at the left side.

5. With the axle level again, add lube P/N 12345841 through the axle housing cover filler hole until it is level with the bottom of the filler hole (approximately 1 litre).

PARTS INFORMATION:

GM PART NUMBER DESCRIPTION -------------- ----------- P/N 12345841 4 LITRES Synthetic Lube

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.