Also the T-Case uses ATF. I have a '89 2.9 auto 4x4 electric shift-on-fly, with for 4.10 gears. Love the truck. I can only hope, wish, and pray that you are lucky enough to have a manual shift T-Case. The shift-on-fly is the most fustrating cluster funk I have ever seen, owned, and hate. If it get wet it may not shift. Or it will shift and then decides that it feels at home and then won't shift out of 4H and like me 4L. It has done that to me twice. I was fifteen miles from my house and was doing chores for my grandpa at the farm and needed 4L. It shift into 4L great, whent to leave and it wouldn't shift out of 4L. And I had no tolls to take the motor off and shift it by hand. That was an enjoyable drive home. fifteen mile going around twenty miles per hour turning four grand. The 2.9 litre is made for ford by mitsubishi and is a great motor blessed with a few problems. They are notorious for cracked heads. If you start losing coolant get it fixed, don't even try a selage yard, I have never seen a 2.9 that had set for more then a few days that still had heads. Go aftermarket. Also they suffer from lifter noise. This is caused because os a poor oiling design to the lifters. I will be honest on cold starts my truck sounds like a SBC with three-hundred grand on it, a few quarts low on oil with straight eighty wieght in the sump, plus a few bent rods, all the main's on the rurge to all spin, starting after a double can shot of John Deere 80% ether starting fluid at thirty below zero, some times. I have had that noise problem twice.