Your chassis in the car includes ball joints, which connect the spring strut and wishbone. They usually work without you noticing anything. However, you should know how these work in order to recognize when a ball joint is defective. This is the only way it can be renewed promptly in order to avoid extensive consequential damage. Just like your wishbones, the ball joints are also components that are susceptible to wear. For this reason, we advise you to check them or have them checked at regular intervals. This also applies to the entire wheel suspension.
Contents
The structure of a ball-joint
This type of vehicle part can be found on your steering knuckle, which is about the size of your fist. Some vehicle experts also refer to the ball joint as a guide joint or axle joint. In addition to the fastening elements, it essentially consists of a movable ball joint and a ball pin, which is usually designed as a pin. In general, however, there are different variants of ball joints, which are used depending on the type of suspension. The simplest type of ball joint is the ball joint. You will find this primarily in so-called McPherson wheel suspensions. Another type of component are real ball joints, which also absorb the full wheel load. In addition to damper strut front axles, you will also find them used in multi-link suspensions.
How does a ball-joint work in a car?
You can think of the whole thing like a shoulder joint. The ball is usually made from the light metal aluminum or from forged steel. The pan that goes with it is also made from the same material. The play-free connection of these two components ensures the correct function and enables the desired tilting and rotating movements. Plastic inserts with a resilient function and the appropriate lubrication ensure that there is no undesired play. It is attached to the corresponding wishbone by riveting, pressing or screwing. A corresponding rubber sleeve ensures that the lubricant stays where it belongs.
How do you recognize a defect in a ball joint?
In general, ball joints are vehicle parts which, depending on the stress, can work for a long time without errors. Their service life depends on driving style, but also on the condition of the road. This usually reaches 60,000 to 100,000 kilometers. In most cases, you can identify defects in these vehicle parts very quickly, as very noticeable symptoms appear. However, these can cover a wide range and range from asymmetric tire wear to a lack of vehicle steerability. In addition, the force required to steer often increases. Basically, instabilities can occur when driving through curves or when driving straight ahead. Finally, worn guide joints or ball joints can also produce unusual cracking noises in the front axle area. If you notice these symptoms or just some of these symptoms in your vehicle, you should urgently check your ball joints yourself or have them checked.
The consequence of such a defect is that the ability of your car to keep in lane deteriorates significantly. You should therefore always take the symptoms described seriously, although defective wheel bearings can also lead to a similar picture. Long-term damage can occur if you do not (or have) replace the broken vehicle components in a timely manner. This can result in damage to the entire axle suspension, which can make expensive repairs necessary.
How can I check myself if my support joints are worn?
Before you commission a professional from the specialist workshop of your choice to repair your axle suspension or your ball joints, it is always worth checking for yourself whether and which components are defective. This makes it easier for you to classify the diagnostic results that your specialist workshop gives you. In general, the replacement of such safety-relevant components should only be carried out by people who have the relevant specialist knowledge and the necessary experience. But how does a general check of your ball joints work?
First of all, you should take a closer look at the components. Among other things, attention is paid to the so-called dust protection sleeves or caps. If these show cracks, dirt can quickly penetrate or the necessary lubricant is lost. Both lead sooner or later to component failure. You should therefore always replace cracked dust caps immediately or have them replaced.
In a next step you need a helper. This should move the wheels as quickly and jerkily as possible (through the steering), because then you can easily notice if the ball pivot of your suspension ball joint has unwanted free play.
Now you have to raise your vehicle to be able to continue the diagnosis. You then have to prepare a support (e.g. a trestle) and place it under the housing of the ball joint to be tested. Then you lower your car far enough that the ball joint rests on the support. The wheel, on the other hand, should still not have any contact with the ground and should remain freely rotatable. As a result, your assistant should press the brake pedal while you try to move the vehicle wheel with your hand. Sometimes it is necessary to repeat this in different wheel positions because the free play can differ depending on the wheel position.
In a last step you take a tire iron to hand. Then you put the flat side right between your steering knuckle and the suspension arm. Now you can press down the other tire iron side. By observing the movement of the ball joint, you can quickly identify possible defects.
Conclusion
To ensure that your vehicle always has the desired performance, a functioning steering and wheel suspension are very important. This is the only way to ensure that your wheels are also guided on the desired curved track. In addition, there must also be a suitable and three-dimensionally flexible connection to the spring strut. This article gives you the basics to identify a worn ball joint. In this way, you ensure timely replacement and prevent it from suddenly separating, because this poses the risk of your wheel suddenly turning sideways.
A tip from CarTipsandmore: postpone a repair of this component not on the long bench. Because a complete failure can quickly become life-threatening. You should therefore visit a workshop if you suspect a defect in your ball joint. The same applies if you have identified a worn ball joint with our instructions. This means that a quick replacement is possible, which can sometimes be replaced within half an hour with the right tool. This applies at least to a ball joint, which is mainly used as a guide joint.