Rear control arms are one of the most important suspension modifications that can be done to your GM vehicle. Stock control arms are on the borderline of junk, bushing deflection and rusting weak stamped material add for traction loss and poor handling ability. UMI boxed control arms are designed to give you the best of both worlds, whether your car is a weekend cruiser or a weekend track addict we got you covered. The included Energy Suspension polyurethane bushings are an excellent improvement over OEM rubber bushings, while adding ride improvements they also work excellent to reduce traction loss. These control arms are a direct bolt-on replacement designed to minimize wheel hop, improve cornering and help track consistency. Each control arm features the correct provisions for adding a stock or aftermarket sway bar. Sway bar holes are reinforced with a 0.120" wall thickness steel sleeve TIG welded and sanded into place. The construction of the control arms features 0.120" wall thickness rectangular tubing with CNC machined drawn over mandrel bushing holders and MIG welded end caps to keep out unwanted road debris.