Anti-roll bar link replacement

How to tell an anti-roll bar link is worn

The most common symptom is a knock heard at low speed. Book a time if you notice any of these:

• There is a knock or clunk from the front or the rear over speed bumps, potholes and cobbles, often from one side only.
• There is a clunk when you drive at an angle over a kerb or into a driveway, that is, when one wheel rises before the other.
• The body leans more than usual in corners. That can mean a link has broken.
• The joint's rubber boot is torn, with grease around it.

A worn anti-roll bar link is not usually felt in the steering. If the steering is loose or the car wanders in ruts, the cause is more likely a track rod end, a ball joint or the control arm bushes. The anti-roll bar bushes and a shock absorber top mount cause a similar knock, and a loose exhaust heat shield is easily mistaken for a suspension fault. So we look on the lift for where the noise comes from before we replace anything.

When an anti-roll bar link is replaced

An anti-roll bar link has no replacement interval in kilometres or years. It is replaced when the joint has play, the boot is broken or the rod has broken. Many links last more than 100 000 km. When a link is replaced, the odometer often reads 140 000–250 000 km. Salted roads, frost-damaged streets and speed bumps wear the joints faster.

Anti-roll bar links do not have to be replaced in pairs. The joint on the other side has as many kilometres behind it, though, so we check it at the same time. If it is worn as well, both are worth replacing at the same visit, because the car is already on the lift.

Replacing an anti-roll bar link does not change the wheel angles. So the toe does not need setting after the replacement, unlike with a track rod end.

How the work is done

1. We lift the car and check the suspension. We move the links, the anti-roll bar bushes, the ball joints and the control arm bushes and see where the play is. We tell you what we found and what the work costs. The work starts only once you have accepted the price.
2. We remove the wheel and undo the nuts at the top and bottom of the link.
3. The joint's stud often spins with the nut. Then we hold the stud still by the hex socket in its end or by its spanner flats.
4. We fit the new link and tighten the new nuts to the manufacturer's torque.
5. We refit the wheel and tighten the wheel bolts to torque.
6. Finally we road test the car over speed bumps to make sure the knock has gone.

On a car driven on salted roads, the nut has often rusted onto the stud. If it will not undo, we cut the nut or the stud, since the old link is coming out anyway. Sometimes rust has also eaten into the mounting point on the shock absorber or the control arm. Then we tell you what the repair needs and what it costs before we carry on.

How long it takes

Replacing one anti-roll bar link takes less than half an hour on many cars. With the check on the lift and the road test included, it usually takes less than an hour. It takes longer if the nuts have rusted in place or if the links are replaced on both sides. We agree when the car will be ready at the same time as the price.

What the price depends on

The price of an anti-roll bar link replacement varies from car to car. It depends on:

• Front or rear. On most cars the front link is easy to reach. At the rear the mounting is sometimes in a tighter spot, and the work takes longer.
• One side or both. If both links are worn, they are replaced at the same visit.
• Rust. A nut or stud rusted in place adds work.
• Parts. Original and aftermarket parts differ in price. We tell you which parts we use.

So we check the car and tell you the price before the work starts.

The anti-roll bar link and the inspection

At the inspection the anti-roll bar mountings are checked by eye, on a play detector and by rocking by hand. Under Traficom's inspection regulation, a mounting counts as having play when the play exceeds one millimetre. For a mounting with play, the inspector gives a repair notice or fails the car, depending on how serious the fault is. If the anti-roll bar has come loose, the car fails, and in a dangerous case it is also banned from the road.

A repair notice does not stop the car from passing, but the law says the fault must be repaired within a reasonable time. A car that failed must be repaired as soon as possible and taken to the re-inspection within a month.

According to Traficom's statistics, in the periodic inspections of passenger cars in 2025 a fault in the front axle was grounds for a fail 126 260 times. That is about 16 % of all grounds for a fail, and among inspection items the front axle was the most common reason for a fail. On top of that, 54 334 repair notices were given for the front axle. For the rear axle, 51 338 grounds for a fail and 13 731 repair notices were recorded. The anti-roll bar mounting is one of the parts checked under these items, but the statistics do not say how many of the faults concerned anti-roll bar links.

On the inspection certificate the fault is often written like this: «Kallistuksen vakaajan kiinnitys, välyksellinen, oikealla edessä ulompi, yhdystanko» (anti-roll bar mounting, play, front right outer, link). The outer mounting usually means the link, and the inner one the anti-roll bar bush. Bring the certificate with you, and we see straight away which side and which mounting it is. If the certificate names other faults too, our inspection repairs cover the whole fault list.

What you can check yourself

• Turn the steering wheel to full lock and look behind the front wheel with a torch. The link is a short rod, usually close to vertical, between the end of the anti-roll bar and the shock absorber or control arm. If the joint's rubber boot is torn or there is grease around it, the joint will soon wear loose.
• Drive slowly over a speed bump or a kerb with the window open and listen for which side and which end of the car the noise comes from. Tell us when you book.
• With the car standing on its wheels, you can take hold of the link and try whether it moves at its joint. If the joint clunks when moved by hand, it is worn.
• Leave the closer check to us. Do not go under a car that stands on a jack.

When not to drive the car

A car with a knocking anti-roll bar link can usually be driven to the workshop, but book a time soon. A joint with play wears further quickly, and in the end the joint can come apart or the rod break. Do not keep driving if

• the link has broken and the end of the rod swings loose
• the knock has turned into hard banging, or there is a sound of metal scraping from underneath
• the car leans clearly more than before in corners
• the inspector has banned the car from the road.

A rod swinging loose can hit the brake hose or the ABS sensor wire. A car under a driving ban may not be driven until the fault has been repaired and the car has passed the inspection. In that case the car comes to the workshop on a tow truck, unless the inspection station has issued a certificate that says where and how the car may be moved for repair. If you are not sure whether the car can be driven, call us before you set off.