2008 Chevrolet Avalanche Owner's Manual - Page 396

How to Check Lubricant What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 6-12. Four-Wheel Drive Lubricant checks in this section also apply to these vehicles. There are two additional systems that need lubrication. Transfer Case When to Check Lubricant It is not necessary to regularly check transfer case fluid unless you suspect there is a leak, or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired. To get an accurate reading, the vehicle should be on a level surface. • For 5.3L engines, the proper level is from 0.04 inch to 0.75 inch (1.0 mm to 19.0 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level. • For 6.0L engines, the proper level is from 0.6 inch to 1.6 inches (15 mm to 40 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level. 5-46