Ned to change the oil in transfer case

The Z71 typically comes with the auto 4wd transfer case (cannot remember the GM number). This requires AutoTrak II, which is available at a GM dealer. Do not use any other fluid in this transfer case! The previous post was correct in the location of the two plugs, but not on the fluid (the other types of transfer cases by GM use ATF). The transfer case is located under the truck right under the cab. There is a small skid plate under it, and a large driveshaft leaves the rear end of the case heading to the rear differential (axle). If you have the manual or electronic w/o auto 4WD transfer case, you can use Dexron III, but Dexron VI is a better fluid that is also now available at your local auto parts store. Again, if you have the AUTO 4WD button in the dash, use the AutoTrak II fluid from the dealer.

There are 2 drain plugs on on the bottom to drain and one about half way up the side of the case to fill it. remember to use the right oil to refill it. 80/90 weight or if yours uses synthetic 50 weight or 75/90 weight