Lubricant Level Inspection - Rear Drive Axle (9.75 Inch Axle)

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Raise the vehicle. Refer to LIFTING AND JACKING THE VEHICLE in General Information.
Ensure the vehicle is level.
Inspect the rear axle for leaks. Repair as necessary.
Clean the area around the rear axle fill plug.
Remove the rear axle fill plug.
Inspect the lubricant level.
Specification

The lubricant level should be between 0-6 mm (0-0.25 in) below the fill plug opening.
If the level is low, add lubricant the until level is even with the bottom edge of the fill plug opening. Use the proper fluid.
NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
Install the rear axle fill plug.
Tighten

Tighten the rear axle fill plug to 21 N.m (15 lb ft).
Lower the vehicle.

Fig 1: Removing Rear Axle Fill Plug - Rear Drive Axle (9.75 Inch Axle)
Courtesy of GENERAL MOTORS CORP.