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ball joint
What is the main function of ball joints? They permit a vehicle’s front wheels to move upward and downward to draw in bumps in roads and pivot for steering. The concept of how they work is similar to that of the joint of ball and socket in your hip or shoulder. They play vital roles in the steering and suspension of your car. Car owners should keep in mind that these joints may break down over time. When they begin to loosen, you will notice it because there is a dull sound produced from the front part of your automobile.
How do you check a ball joint? Here are the steps on how you can properly do the inspection. You should find time to read and take these steps so that you will not experience suspension or steering problems with your car. The first step is to refer to the service manual of your car. This reference contains all the necessary information as regards to the repair of your car and measures for you to adopt to prevent problems in the future. Manufacturers of automobiles build a variety of suspension setups which can be of big help to you. Therefore, read the manual carefully to find out what type of ball and socket joints used by your car.
The second thing to do is find a wear indicator. While your car is stationary, take a look underneath it specifically on the steering knuckle’s bottom part. The said knuckle is attached to your car’s wheel. The most widely used indicator is basically a grease fitting which doubles as an indicator of wear. This fitting will stick from the bottom of the housing of joint by nearly half an inch. When it wears, the fitting will move back into the housing. The joint must be fine as long as the fitting projects out. In the event that the fitting has receded, you will need to have the ball joint replaced with a new one then. If you really cannot find an indicator of wear or if the indicator is not efficient in terms of giving you a clear sign, you may proceed to the third step.
The third step to consider is raising your car’s front end. Position a hydraulic brace or jack underneath the front wheel’s lower control arm. You should see to it that the jack is positioned as close to the ball joint as possible. Raise your car till the wheel gets off the ground. You should see to it that no compression is in the suspension as you inspect the joint. In case that the control arms do not have equal lengths, the upper bump stop should not be brought into contact with the control arm. If there is a McPherson strut, let it project as far out as possible.
The fourth step is rocking the wheels and inspecting for play. However, there is a certain required amount of movement you can cause to the wheels and it is specified in the service manual of your car. There are two basic plays you can have for your car: side-to-side and vertical. For side-to-side, a dial indicator is needed. It is an instrument used in measuring the amount of play. Place this instrument inside the rim of the wheel close to the ball joint. Pull the wheel at one side or the other to have it pushed in and pulled out laterally. For the vertical play, position the instrument against the housing of the joint or steering knuckle nut. Pull the wheel at the bottom and top to pull it down and lift it up respectively. Read the indicator and compare the results with specifications of the manufacturer. If the movement is beyond what is specified by the manufacturer, the joint needs to be replaced. Repeat this step for the other front wheel.