2001 chevy silverado 2500 hd 4x4 gas. I have a low rubmle or thump in suspension on dirt roads ( which I live on) I have 56,000 easy use miles on this one owner truck. Is there a suspension bushing on an antisway bar or trailing arm that is rubber and needs replacing? The noise is not rpm related. I have new shocks new tires and no steering alignment problems
See if it's bottoming the control arms will have spots were the bump stop hits. Can't help that
If it's really a thud.
Lift a side of the car and pop a crow bar under the wheel and see if the lower ball joint moves. Wiggle the tire in and out to check the upper ball jont. Other wise pry the crow bar into all the control arms and see if they move. The rest of it could be cheaked by rattling them.