The ball joints--one on each side--are key components in the suspension of the front end on most vehicles. Whether you drive a car, truck, SUV or minivan, it probably has ball joints. These strong, steel pivot points connect the steering linkage and the axle assembly. There are several signs you can look for to know when the ball joints are bad. For safety sake, the ball joints should be inspected on a regular basis.
Take your vehicle out on the highway for a test drive. You may hear odd noises in the front end. These could mean the ball joints are bad, especially if you hear clunking noises. Yet, the noises could mean there's something else wrong, so you have to pin it down.
Place both hands on the steering wheel as you're driving. If you feel a shimmy or a vibration in the front end of your vehicle, that could mean the ball joints need replacing, especially if the vehicle is hard to handle or if the steering feels loose.
Remove your hands from the steering wheel while you're driving on a straight stretch of road. If your vehicle wanders instead of going straight, this could mean the ball joints are bad. Your vehicle may pull to one side too.
Park your vehicle on a flat surface and turn the steering wheel to the left. Inspect the front tires. If you see/feel cupping on the edges of either tire, the ball joints may need replaced. Cupping is abnormal wear on the tire. It's high and low spots on the tread.
Park the vehicle on a hard, flat surface. Jack it up so that both front tires are off the ground. Grab the top and bottom of each tire and try to rock it back and forth. If either wheel moves, that's a good sign the ball joints are bad and need to be replaced immediately.
Ball joints in a vehicle can't be adjusted or repaired. When one is bad, then both sides need to be replaced.
If you can't replace the ball joints right away, then you should park the vehicle. If you can't do that, then drive slowly and be prepared. Once a ball joint breaks, you'll no longer have complete steering control.