There are many reasons to replace the front or rear control arm assembly, the most common of which are worn-out bushings or ball joints and rust. A typical stamped steel control arm will show signs of rust and corrosion. The life expectancy can be shortened due to exposure to water and road salt.
There are three different types of control arms. Stamped steel is lightest and more economical; however, it will deteriorate from rust over time. Cast iron is extremely strong and can withstand harsh environments better than the stamped steel control arms, but are typically found on truck applications. Last, cast aluminum doesn’t corrode quite like steel control arms do, but since aluminum is a softer metal, they do bend and crack from road hazards. With that said, look for a stamped steel control arm that is E-coated to withstand the elements. This will make for a longer-lasting product and repair for your customers’ vehicles.
Courtesy of Autopart International.