The rear springs get tired over time and the T-bars do the same.
It sounds like you are ready for some Alcans in the rear and Sway-A-ways up front.
New shocks would also be a good thing.

I did all of that and a little more on my '96 @ about 75K, I now have just over 196K and my truck is tight and level. <img src="/forums/images/graemlins/cheers.gif" alt="" />

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