Springs & Top Mounts

Check the last coil first. Broken springs usually fail within the final turn near the lower seat, and the broken end can sit close enough to its neighbour that the car drops only slightly, so the fracture is easy to miss without looking directly at the coil. Corrosion pitting on the wire is the warning sign. A sag without a break is far less common than most people assume, since modern springs fatigue and snap rather than gradually settling.

Usually the upper mount rather than anything to do with the spring. The mount is a bonded rubber component isolating the strut from the body, and when the rubber separates from its metal or the internal stop wears, you get a knock over bumps and often a creak on turning as well. Have somebody turn the wheel slowly while you rest a hand on the mount from inside the engine bay or boot: roughness or a click as it rotates points at the bearing beneath it.

Yes, across the axle. Springs settle very slightly with age and a new one alongside an older one leaves the car standing unevenly, which shows up as a corner that sits high and an alignment that will not come right. Doing both also means the rate is matched side to side, which matters for how the car behaves in a corner. The labour is largely shared, since the same tools and the same setup cover both sides.

Order them with the spring. The pads sit between the coil and its metal seat at each end, stopping the spring ringing against the seat and keeping water out of the contact area, and they are usually flattened, split or missing by the time a spring has failed. Fitting a new spring onto a perished pad reintroduces the corrosion path that broke the last one. They are inexpensive, and this category lists upper and lower pads for both axles separately.

It lets the entire strut rotate as the front wheels steer, since the spring and damper turn with the hub carrier on a strut suspension. When it dries out or corrodes, the strut binds instead of turning smoothly, which produces a creak or graunch at parking speeds, a steering wheel that does not self centre cleanly, and sometimes a notchy feel through the rim. It is a cheap part, listed here as a front strut bearing assembly, and it is worth replacing whenever a strut is dismantled.

It needs prompt attention rather than panic. The immediate risk is that the broken end, which is a sharp piece of hardened steel, can contact and cut the tyre sidewall, and on some designs the loose section can foul the damper or the driveshaft. Handling also suffers, with the car sitting unevenly and the affected corner losing control. Drive gently and directly to a workshop, and replace both springs on that axle rather than only the broken one.

Cushion pads, spring seats and support pads sit right at the bottom of the range, and strut bearings are only slightly above them. Coil springs are moderate. Strut upper mount assemblies cost more, particularly where they incorporate the bearing. The live minimum and maximum are shown in the band at the top of this page. Since springs are bought in axle pairs and pads should go with them, price the whole set for one axle rather than a single item.

Only with a proper spring compressor and a healthy respect for what a compressed spring stores. The energy involved is enough to cause serious injury if a compressor slips or is fitted to too few coils, and improvised clamps are the usual reason that happens. If you are working on a strut, either use correct professional tooling or buy a complete strut assembly with the spring already fitted, which removes the compression step entirely. Rear springs on some designs come out with the axle lowered and no compression at all.

They change more than ride height. Reducing ride height moves camber, toe and roll centre, shortens the available damper travel so the bump stops carry more of the work, and on many vehicles puts the driveshafts and arms at angles they were not designed for. Cars with driver assistance also have camera and radar aiming referenced to standard ride height. If ride height is changed, an alignment and a driver assistance calibration are both needed, and the factory springs remain the safer purchase for a road car.

Look at what it was sitting on. A spring fitted onto a corroded or damaged seat, or without its cushion pads, sits slightly off centre and concentrates stress in the last coil, which is exactly where fatigue cracks start. Grit trapped in the seat does the same by scratching the protective coating. Clean and inspect both seats, replace the pads, and check that the coil end is correctly located in its seat pocket before the strut goes back together.

They may fit and leave the car sitting at the wrong height. Spring rate and free length are matched to vehicle weight and suspension specification, so a spring from a lighter or lower specification version of the same body will change ride height and handling with no fault code to explain it, and battery electric versions are usually heavier than their combustion equivalents. Match the OE number from the old part, and use the quote form where the reference brings back nothing.

Yes. Coil springs come in rate variants for different equipment levels on the same model, and the heavier duty or rarer rates are the ones that wait for a quote. Send the number and say which axle. Springs are ordered in pairs, since a replacement on one side alone leaves the car sitting unevenly and loads the anti roll bar. Add the top mount, the bearing and the bump stop to the request. Those come apart with the strut anyway, the bearing is what makes the steering notchy, and none of them is expensive next to doing the job twice.