Rebuilding your front suspension? Here's usually the most difficult part to get right-the lower control arm. The lower control arm pivots on the pivot shaft (left). The pivot shaft bolts solidly to the K-member and doesn't budge, while the torsion-bar socket rotates with the control arm. Torsional deflection in the lower control arm's inner rubber bushing is the only thing that lets it rotate for suspension travel. Replacing the lower control-arm bushing is the number-one source of misery in rebuilding a Mopar frontend, unless you know the tricks.