BMW X4 Suspension Control Arm Bushings Replacement Cost

Control arm bushings are found between the control arm and the body or suspension subframe. The bushings help distribute impact force and absorb vibration. 

If the bushings are worn out, the suspension will make a squeaking sound when going over bumps. If they are severely worn, a knocking sound may be heard as the control arm makes metal-to-metal contact with the bushing bracket. With severely worn bushings, tire wear may be uneven and the vehicle may pull to one side or wander.

If the control arm bushings are worn, the result will be an annoying squeak when the car goes over bumps. In this case, the car can be driven. But if the bushings wear out considerably, metal-on-metal contact may occur and cause further suspension damage and inconsistent handling. This requires a repair.

While there's no set schedule, the bushings may wear out and need to be replaced as a vehicle approaches 100,000 miles. Driving aggressively or over rough roads can decrease the lifespan of the control arm bushings. On some vehicle models, the bushings are permanently installed in the control arms. If the bushings wear out, the entire arm will need to be replaced.

A technician may diagnose a worn lower control arm bushing during a test drive of the vehicle. The condition may also present itself during a bounce test, where the technician will press down firmly on one corner of the front end of the vehicle to bounce the suspension and pivot the control arms. A severely worn control arm bushing may also show up during a four-wheel suspension alignment since the control arm determines the position and angle of the wheel.

The car must be lifted, and the wheel and tire removed. The lower control arm must be disconnected from the lower ball joint and the vehicle frame or body. An upper control arm is disconnected from the strut tower on the body and from the top of the steering knuckle. It's common to replace related components, such as ball joints, tie rod ends and sway bar links, at the same time a control arm or bushing is replaced.

On many vehicles, the control arm bushings are not replaced separately and may need to be replaced along with the control arm.

A four-wheel alignment will be needed after performing this type of suspension repair.

RepairPal recommends inspecting (and replacing if necessary) the ball joint at the same time that the control arm bushings are replaced. Since the control arm determines the position of the wheel and tire, a wheel alignment is also recommended.