Recently drove my 01 Ram 4X4 2500 Cummins w/99,000 miles, 100 miles on a horrible USFS road that limited speed to 15-20 mph and even then shook the crap out of the truck. Had the front end checked @98,500 and mechanic says ball joints are fine. After that trip, even a slightly rough pavement produces a "thunking" from the front of the truck underneath. I got underneath and tried to wiggle the track arms, steering bar (I have Luke's Link and The Steel steering box stabilizer), exhaust was not hitting anything nor the drive shaft. U joints are fine. All the rubber bushings are quite perished but have been for years. This is far from the first time I have driven on Wyoming's back dirt roads but this noise is new and of concern. Frankly I am gobsmacked as to the cause. Any advice most appreciated.