Suspension Control Arms offer a wide range of adjustment. Engineering Parts offers a full range of high-quality aftermarket chassis and steering parts to meet the needs of installers and vehicle owners. All Engineering chassis components are designed to meet or exceed the original equipment parts fit, form and function. For nearly 30 years, Engineering has designed, engineered, developed and produced some of the most innovative components in the OEM and performance aftermarket industries. Engineering Torsion bar keys are an economical way to give your truck some front end lift. Designed to work with trucks that have a torsion bar front end, torsion keys provide lift without having to crank up the factory torsion bars.