The 2001 Chevrolet Tahoe offers three differential options; a 10.5-inch Dana rear end, a 9.5-inch standard differential, and a 11.5-inch standard differential. Several models of the Tahoe offer a full-time or selectable four-wheel drive which includes a front differential and transfer case. Always check front differential and transfer case if equipped when servicing the rear differential.
The rear differential calls for SAE 75w90 gear lube. The selectable four-wheel drive front differential uses SAE 80w90 whereas the full-time four-wheel drive option uses SAE 75w90. The weight difference between the two is interchangeable should one not be available. Chevrolet recommends synthetic or long-life variations of the fluid for vehicles with higher-mileage or extensive use.
The front differential fills at 3.6 pints. The 10.5-Dana and 9.5-standard differential use 5.5 pints to fill. The 11.5-standard differential needs 7.7 pints. Front and rear differentials use a 3/8-inch socket fill plug located on the differential facing the engine. Fill the cases to just beneath the fill line when adding fluid.
Use a long, thin screwdriver or an L-shaped Allen wrench to check the fluid level within the differential. Insert the tool into the fill plug hole and twist it slightly. The tool should have a little fluid on the tip if the case is full. Fill as necessary. Check the transfer case when checking the differential. Checking the fluid level is the same. Replacement fluid for the transfer case is synthetic multi-vehicle automatic transmission fluid (ATF).
