Upper & Lower Control Arms & what they do..control Arms are the most mis-understood component of a suspension system. Follow these guidelines & have proper handling & prevent rapid treadwear Factory arms are perfectly engineered to maintain proper Geometry in relationship to the height of the vehicle. Any variation of as little as 1/2 an inch will change your Geometry and it will be necessary to realign to maintain your Toe-in, Caster, and Camber. All of our control arms are manufactured using state of the art CNC cutting, bending and forming processes with high strength steel plate and DOM Steel Tubing. We manufacture our ball joint mounts out of steel plate ranging from 0.375” to 0.500” thick and some control arms are made using CNC Turned steel ball joint cups. All of our tubular control arms made using 1.0” dia. – 1.75” dia. x 0.120” - 0.188” wall DOM Steel Tubing that is precision bent, coped and Mig/tig welded by the best welders in the industry.