Hi, This may sound like a dumb question but here goes. I have a 2000 (old body) K2500 what fluid should be used in the transfer case. The owners manual say ATF for standard case and special stuff for auto transfer case. What do they mean buy auto transfer case, they aren't just refering to push button as auto or did the older trucks come with an auto 4x4 option.

the some of the 1500 trucks came with an "auto" 4WD. It will say Auto on the button.

Yes what Accord said!!