2007 Chevrolet Tahoe Owner's Manual - Page 497

• 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. • The proper fill level for the 2500 Series is from 0 to 1/2 inch (0 to 13 mm) below the bottom of the filler plug hole, located at the front of the axle. Add only enough fluid to reach the proper level. How to Check Lubricant Four-Wheel Drive Lubricant checks in this section also apply to these vehicles. There are two additional systems that need lubrication. Automatic Transfer Case 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. If the level is below the bottom of the filler plug hole, you will need to add some lubricant. Add enough lubricant to raise the level to the bottom of the filler plug hole. Use care not to overtighten the plug. When to Change Lubricant Refer to the Maintenance Schedule to determine how often to change the lubricant. See Scheduled Maintenance on page 579. 497