The term "ball joint" refers to any one of hundreds of joints that make up a tubular shaft with two ends. While most use a ball joint as a synonym for "shaft joint," it should not be confused with a rubber or plastic bushing. Rather, a spherical ball joint typically is made out of steel or other metal to allow it to rotate between various bearing arrangements.
Unlike a rubber bushing, however, a ball joint is designed to rotate in multiple planes. In fact, as the ball joint continually pivots in different angles, it's often prone to breakage more easily than do fixed heims. Fortunately, though, ball joints are available in several different types that tend to suit different applications. Of course, all ball joints function by allowing the axle to move between different pairs of rollers or wheels.
One type of ball joint commonly used in axles is the camber adjustment joint. Also called a lip joint camber adjustment ball joints are designed to provide mild or moderate degrees of camber between two drive axles. Because this arrangement requires a certain amount of tilt in the center of the vehicle, it is often found on small trucks and mid-sized cars. Caring for these ball joints can be a challenge. They need to be properly oiled on a regular basis and must be kept free of debris. Fortunately, as long as the camber is adjusted just right, most vehicles can perform with care and have relatively limited cosmetic impact.
A second common type of suspension system used on trucks and cars is the heim joint. A heim joint is simply one of several rotary vanes that are installed on a suspension arm. A heim joint typically features three to four balls that are arranged vertically inside a specially shaped slot. Heim joints are an excellent choice for light trucks with minimal passenger capacity. They can also be used to help increase the width of sports cars or for maximally effective off road applications.
Another way to test your alignment while using an alignment lift is to attach a dial indicator to the lower control arm and then place the ball joint on the alignment jack stand. This is done while the vehicle is parked, and the jack stand raised to level the joint. By measuring the height of the dial in a straight line between the center of the jack point and the pointer on the alignment indicators, you will determine whether the joint is sitting correctly in reference to its intended location. If the indicator points to the left, the joint is too high; if it points to the right, the joint is too low.
Once the joints have been installed, you may notice some minor wear, but this is not uncommon. The most common cause of minor wear is poor maintenance. A small amount of wear is normal and acceptable as long as it does not interfere with your ability to drive the vehicle. If you detect excessive wear or if there is rust developing under the ball joints, contact the manufacturer to request replacement.
The third parameter associated with ball joint wear is the angle of the spine. Most vehicles have a standard V-shaped angle where the joint sits, but you may find some vehicles are manufactured with a special angle or extension. The angle of the spine can vary, depending on the type of driving conditions. For instance, when driving up a hill, the turning radius increases due to the increased ground clearance and when cornering, the angle of the spine may decrease due to the increased steering traction.
To keep your automobile's suspension in good condition, lubricate both the ball joints and heim joints regularly with high quality engine oil. The oil will help protect the bearings from rust buildup and rust damage. If you are experiencing any abnormal wear in your suspension, consult a professional to identify the problem. A spherical bearing may be causing the problem, so the only logical solution is to replace the entire suspension system.