Symptoms of a Bad Control Arm

Timely replacement is crucial. Here are common signs of control arm failure:

• Clunking or knocking noises while driving over bumps
• Steering wheel vibration at higher speeds
• The vehicle is pulling to one side
• Uneven tire wear
• Loose or wandering steering

If these symptoms appear, the control arm or its bushings/ball joints may be worn or damaged.

When and Why to Replace Control Arms

Control arms generally last 80,000–150,000 kilometers, depending on driving conditions and load. It’s important to:

• Replace them if any signs of cracking, bending, or bushing failure appear
• Check them during major suspension overhauls
• Use high-quality replacements that meet or exceed OEM specs to ensure safety

How to diagnose control arm problems?

A technician may diagnose control arm wear during a test drive of the vehicle. It may also be seen during a hop test, where the technician pushes hard on one corner of the vehicle to bounce the suspension and rotate the control arm. Because control arms determine the position and angle of the wheels, a damaged or bent control arm may be discovered during a four-wheel suspension alignment.

How is a control arm replaced?

The technician will first lift the vehicle in the air and then remove the wheel and tire before replacing the lower control arm. The lower control arm must be disconnected from the lower ball joint (which is attached to the steering knuckle) and the frame or body of the vehicle. The upper control arm is disconnected from the strut tower on the body and the top of the steering knuckle. Some control arms have built-in bushings, while others require bushings to be installed. When replacing a control arm, related parts such as the ball joint, tie rod joint, and stabilizer link are usually replaced at the same time.