Prothane front spring bushings for 1973–1986 GM K10–30 4WD trucks replace worn rubber with black polyurethane components to restore suspension alignment and reduce deflection. These direct-replacement bushings improve spring stability and longevity compared with stock parts, making them a practical upgrade for older trucks that need firmer spring support without changing ride geometry.
Prothane 73-86 GM K10-30 4wd Front Spring Bushings - Black