Ball joints are an integral suspension component in most modern vehicles. They are bearings located in a socket and are the main suspension pivot point. Think of the human hip and how the femur connects to the pelvis socket. Ball joints are what interlock the control arm to the steering knuckle or connect the vehicle's tire and steering wheel to the suspension. The allow the pivot between the steering wheel and the suspension.
As a vehicle owner, it is normal for you to want to know more about ball joints and how you can tell if they need to be replaced.
How Often Should You Replace Ball Joints?
Replacing the ball joints on your vehicle is not considered a part of routine, preventative auto maintenance. A good rule of thumb is to have them checked by a mechanic every time you take the vehicle in for an oil change. If the ball joint is sealed, it will not require grease. If the ball joint is not sealed, you should have it greased every time you change the oil.
How Can You Tell When They Are Going Bad?
The front ball joint permits the wheels and the suspension to bounce up and down as well as move back and forth, allowing a vehicle to be more flexible and not as rigid. The ball joints are made of a steel ball with a tapered stud coming out of it. It is covered in a lubricated metal socket or housing. Ball joints are built to last a long time, but they can wear out and break just like every other part of your vehicle.
Clunking Noise: If the front ball joints go bad a clunking noise can be heard from the front of the car. As the ball joints wear out they become loose and will clunk around when the vehicle moves over rough roads or when turning. The noise can increase as the ball joints become more worn.
Extreme Vibration: Another symptom of worn ball joints is extreme vibration coming from the suspension. When the ball joint becomes loose in its socket they will vibrate as they move when the vehicle is in drive.
Drifting Vehicle: If the vehicle drifts off to the side, then that could also be a sign of loose ball joints. When the ball joints are in working order, and the vehicle has good alignment the steering wheel should remain straight and properly responds to when the wheel is turned. If the ball joints or alignment are out the steering wheel can begin to pull in either direction, which can cause the driver to have to steer differently to compensate.
Uneven Tire: Uneven tire wear can also be a sign of worn ball joints. As the vehicle pulls in different directions the tires withstand different pressure causing different areas to wear out faster than others. Usually wear inside the tire or the tire starts to feather are a sign the ball joints have become worn and are in need of replacing.
If you notice any signs that your ball joints are bad, get them replaced as soon as possible. If you are just bringing your vehicle in for an oil change, consider letting the auto repair shop check the ball joints during the appointment.