What is an anti-roll bar link?

Also known as a sway bar link or stabiliser link, an anti-roll bar link connects the outer ends of the anti-roll bar to the rest of the suspension system via the steering knuckle, transverse control arm or strut. In this way, the link helps to stabilise the vehicle when driving over bumps or potholes, and to prevent body roll when cornering. In most modern cars, the stabiliser links have small ball joints at each end and are connected to bushings. 

The design of the component may vary depending on the type of vehicle. The metal links are usually made from cast iron, steel or alloys so that they are able to withstand impacts when driving. However, over time the ball joints and bushes will be worn down, requiring maintenance. This may cause play in the link joints or vehicle instability when travelling, which is why it is important to respond to faults quickly.

Causes of faults

Here are some of the most common causes of a bad anti-roll bar link:

• Water intrusion

If the component and its joints are regularly exposed to moisture, the metal parts can begin to corrode. In some cases, you may be able to remove the rust and treat the surfaces, but a replacement is required in most cases.

• A lack of lubrication

If the parts aren’t lubricated properly or don’t have enough grease, they will wear out faster.

• Collisions

Like many other car components, the links can get damaged as a result of a collision. This can result in deformation or cause gaps in the joints.

• Aging

This one is fairly self-explanatory. The metal components may last a very long time, but rubber bushings have a limited lifespan. The more stress you put on the suspension (e.g. from cornering at high speeds), the more often you’ll need to replace the parts.

Symptoms of a bad stabiliser link

• Strange sounds when going over bumps or driving at high speeds

If you hear a clunking, rattling or knocking sound coming from around the wheels, it could be due to a faulty anti-roll bar link. The sounds often appear due to the bar coming loose or play in the joints.

• A “loose” steering wheel and handling problems

If the stabiliser links are loose or damaged, the vehicle’s handling performance will be poor. This is especially noticeable when cornering or manoeuvring at high speeds. The steering wheel may feel loose, and the car may begin to drift or sway from left to right. Worn bushes are often the culprit.

• Visual signs of damage

You can conduct a visual inspection of the suspension parts every so often. If there is play in the ball joint or visible damage to the joint’s dust boot, you should get it repaired. You can also check to see whether the bushes are worn or the link is bent out of shape.

Replacement tips for anti-roll bar links

There isn’t a specific replacement interval for all anti-roll bar links, where they have to be replaced after reaching a certain mileage. However, it is strongly recommended to replace the parts as soon as they go bad. Thankfully, these components are inexpensive to repair. For example, it normally costs around  £60-£160 to replace the bushes. If you have the right skillset and tools, you can keep the costs down by replacing the parts yourself.

Replacing the bushes:

• When replacing these parts, you may need to raise the vehicle using a jack and stands or a vehicle lift before removing the wheels to access the links.

• After removing the wheels, jack up the lower control arm on each side of the axle to support it and reduce the weight on the links.

• Unscrew the fasteners which hold the U-clamps in place and make a note of how many there are and where they are located.

• If they are split bushes, you can remove them from the anti-roll component by pulling. If not, you may need to detach the bar from the suspension arm mount and pull the bush along the bar until it comes off. When replacing end bushes, you may have to remove the bar completely.

Frequently Asked Questions (FAQs)

Is it necessary to replace both stabiliser links if only one of them is faulty?

This isn’t always necessary, but it is often recommended due to the fact that both links normally wear out at the same rate.

Do you have to replace the links whenever you replace the struts or control arms?

Not necessarily, no. However, it’s important to note that with older vehicles, it may be difficult to remove the components without damaging them. This is why they are frequently replaced at the same time as the control arm or strut.

Sources of information:

Information about anti-roll bar links from onlinecarparts.co.uk

Tips for replacing anti-roll bar links from howacarworks.com