What's the 2004 Chevy 2500hd rear differential fluid capacity?

The 2004 Chevy 2500HD rear differential holds 2.2 to 4 quarts of fluid depending on the rear axle and gear options on the vehicle. The larger rear axle will hold more fluid than the smaller ones and that is usually used on towing upgrade packages. The rear differential fluid in a 2500HD iS80W gear oil. This is much thicker than the type of oil that You would expect to find in a transmission or engine. This is because a differential is much smaller in size so there is a lot more heat in it. A thinner oil would break down and not be able to protect the gears in the differential as well as the thicker oil.