Bad 2wd front-end handling. Are there parts that wear and should be replaced?

Hi Guys:
My truck rides like hell. It seems to studder and shake when I hit bumps in the road, more so in the front than in the rear. It almost seems like I'm bottoming out the suspension but without a loud "bang" due to the "shifty-ness" of the front end. Here's the details:

98k on my 2wd so far. Picked it up with 93k
- Replaced front shocks with Bilsteins
- Replaced rear shocks with MX6
- Running 40psi of pressure f/r
- Swapped out my front sway bar bushings with Energy greasables
- 265/75 Goodyear tires with fair amount of tread left
- No abuse to the truck that I can find underneath (very little dust/dirt collected behind body panels and the tail-lights, so I don't think it's been offroad much, if at all)

I'm wondering if there are some rubber parts on the 2wd that need to be replaced every few years or so. If so, can you guys tell me WHAT you changed out and what made the most difference? I have a shop with a hoist and can handle whatever needs to be done...I just don't know where to start since it just rides so badly. Part numbers? Any suggestions?

Thanks for anything that you can give me!

Very Sincerely,
Kevin