I've heard that these trucks are supposed to be pretty smooth, but apparently no one told mine that. It's a 2001 Durango RWD SLT Plus with the 4.7 L. It's gotten progressively worse over the last 2 years I've owned the thing. I feel a lot of the road underneath the truck, and it takes speedbumps and potholes way rougher than I know it should. I know it probably needs new upper ball joints/control arms because I can wiggle the front driver's side tire a little when it's jacked up (the tire is mounted to the hub just fine), and the tires won't align perfectly, but I know that can't be the only issue.

Things I've replaced so far:

Rack and pinion

Inner and outer tie rods

Rear tires (now running 255/70R16 Valera H/T's, front tires are Cooper 255/65R16's that are about to get replaced with tires identical to the rears, and none of the tires are running too high of a pressure)

Lower control arms (both sides)

Front and rear shocks (running KYB Gas shocks)

Two front wheel hubs, one rear

What else could be going wrong? I can't tell if the rear leaf springs or the front coil springs are bad, how would I determine that? Could it possibly be the body bushings? I was at a loss after I replaced the shocks and there was no difference. Any help is appreciated.