Pro Comp Pro Runner Upper Control Arms now available for more trucks via Marken Performance. Pro Comp has engineered the new Pro RunnerTM Control Arms utilizing oversized stainless steel FK uniball joints. The big uniball joints provide unparalleled strength over factory ball joints for off road performance. Heavy duty chromoly tubular construction and reinforced pivot bushing mounts are used to eliminate flex and handle the added load from extreme suspension cycling. Large PTMEG pivot bushings are equipped with zerk fittings for easy maintenance and quiet operation.