I don't think it's the driveshaft, it's not a constant vibration. It varies with the road surfaces, and it feels like the wheels are bouncing up and down, like dribbling basketballs low and fast.

I understand about trucks riding like trucks. This isn't a stiff ride, it's shaky. It's also a 2wd 1/2 ton, not a 4wd 3/4 ton that's lifted and has off road tires, so it should ride smoother, like a sedan.

I've replaced -

Shocks (due for new though, next purchase)
Front hubs
Rack and pinion
Inner & outer tie rods, w/alignment
Upper control arms & ball joints
Lower ball joints
Front coil springs (what a bitch! Never again)
Lower steering shaft
Torsion bar links
New tires this winter

It does OK on smooth asphalt, but on slightly rough roads it's awful. There's a stretch on 86 just before I turn off to go to BLGC that I just dread driving on.

I'm mainly wondering if guys here with similar trucks have similar problems.