At bout 70 mph, i get the shakes in my pedals /seat & door panel,,what can be the culprit?

95 2wd 2500 142k auto

 

lots of components/parts worn

 

Tire balance
Bent rim
Mud build up inside the rims
Broken belts in the tire
Wore out shocks
Wore out shock bushings/loose shocks
Bad ball joints
Bad tie rods
U-joints

You ask a very general question, and unless you list what you have checked, no one can help you.

 

Could be as easy as a wheel weight fell off to front end replacement.