Control Arms

Control arms are essential components of a vehicle's suspension system, acting as the links that connect the wheels to the car's frame. There are typically two types: upper and lower control arms. The upper control arm connects to the upper part of the wheel assembly, while the lower control arm connects to the lower part. Together, they help maintain the correct position and alignment of the wheels.

Control Arm Type Suspension

This system features both upper and lower control arms. The upper arm connects the top of the wheel assembly to the vehicle frame, while the lower arm connects the bottom. This configuration allows for better wheel articulation, stability, and handling, especially during cornering.

Strut Type Suspension

In this design, there is typically a lower control arm, but the upper control arm is replaced by a strut assembly. The strut serves as both a shock absorber and a structural component, connecting directly to the wheel spindle. This setup simplifies the design and reduces weight but may not provide the same level of performance as a full control arm suspension.

How Control Arms Work?

Control arms pivot at two bushings attached to the vehicle frame, allowing for vertical movement. The other end connects to a spindle, where the wheel is mounted. In non-strut designs, both control arms connect to the spindle via ball joints, enabling rotation and vertical movement.

A coil spring is typically positioned between the control arm and the vehicle frame, providing support and cushioning. Some control arms may have adjustable attachment points for alignment, allowing mechanics to ensure the wheels are properly aligned for optimal handling and tire wear.