The nut on the rear of the output on mine backed off and its been fixed a few times before I owned it, It broke a cluster gear and other parts when I bought it $1200 later its good! The vac 4wd stink. Replaced my switches twice, next is a cable unit! Otherwise they hold up well with towing
Over the few decades, Ford and Dodge sure did some misleading changes on the "engage the hubs" methods. Not long ago Dodge used a 4x4 engage process that kept the front drive gear turning and disengaged 4x4 in the transfer case vs. at the hubs which turned into a real demolition derby when the front driveshaft double cardigan U joint broke and put holes in the floor boards, damaged crucial wiring and in some case, put holes in the engine block. But, in both cases, the vacuum idea really had their problems as well as the "Uni Bearing" ideas that went from two front wheel bearings (inner /outer) to just one. Those rarely lasted more than 60,000 miles. GM was the only one who kept the changes real for the most part however, 4x4 is most reliable with the mechanical hub engagement design. Warn hubs or those Dynatrac hub kits work best.
