2003 GMC Safari Owner's Manual - Page 270

Rear Axle When to Check Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant. See Part A: Scheduled Maintenance Services on page 6-4. How to Check Lubricant To get an accurate reading, the vehicle should be on a level surface. If the level is below the bottom of the filler plug hole, you'll need to add some lubricant. Add enough lubricant to raise the level to the bottom of the filler plug hole. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Part D: Recommended Fluids and Lubricants on page 6-32. 5-53