My '89 has what is to me an almost ideal powertrain. The AMC 360 is nearly bulletproof and puts up with my crap, the TF727 behind it is stout but lacks overdrive, and the NP229 is adequate for what I do, mostly winter snow driving and some trail duty. The vacuum setup has been replaced with a PTO cable for reliability and ease of maintenance. The twin Dana 44s are well-suited to the heft of the truck and I have no complaints about any part of my Wagoneer except the window regulators and sagging springs.
Heap o Jeep... and over 2 ton o fun...