I purchased my '98 Jimmy in 2012 with 148,000 miles. The previous owner had unplugged the 4x4 switch and when I plugged it in I figured out why. The front wheels engage in four wheel drive quite smoothly in both 4Hi and 4Lo. The issue is when I turn either direction there is a nasty thumping/jumping sound and feel in the steering. Like a drive gear slipping/popping. When I disengage the 4x4 everything is fine. Wondering what the issue is: transfer case, front differential or ?. I live in SW WI and snow is coming. Any ideas on the issue would be appreciated.
