Suspension control arms are commonly referred to as “A arms,” and they’re a major part of the front suspension system. Simply put, the control arms usually connect the front wheels to the car. One end of the control arms will connect to the car’s framework, whereas the other end will connect to the wheel assembly. The upper control arm will connect to the front wheel’s uppermost area, whereas the lower control arm will connect to the front wheel’s lower part. Both arms will then attach to the car’s frame. For those with an independent rear suspension, the design will be similar. Simply put, the control arms will act as a link that will connect the front wheels to the car. Different types of control arms suspensions include:
- Strut type suspension
- Control arm type suspension
The strut-type designs usually have a lower control arm, and they won’t have an upper control arm. The strut designs will serve as the upper control arm, and it may be connected directly to the lower control arm or spindle.
How does the control arm work?
The arms will be tied on the side of the frame to pivot down and up on the bushings of the control arm. By doing so, it’s possible to combine two opposite motions. The control arm will be tied to the front wheel and the spindle with the lower and upper ball joints on the opposite side. The coil spring will support the car’s weight, and the shock of the road surfaces will be dampened. For the bushings, ball joints, and control arms to be in perfect alignment, the control arms will have adjustable attachment points, and they’ll be placed at the frame. If necessary, the mechanic can align the end and front such that the car can drive straight along the road.