The rear axle oil level needs to be between 1/8 in (3 mm) below the bottom of the fill hole and the bottom of the fill hole.

The rear axle fill and drain plugs should be tightened to 22 to 29 ft lbs (30 to 40 N·m) on axles with aluminum housings. The rear axle fill and drain plugs should be tightened to 22 to 52 ft lbs (30 to 70 N·m) on axles with cast iron housings.

CAUTION!
Do not over tighten the plugs as it could damage then and cause them to leak.