Alloy wheel corrosion: what causes it, is it dangerous, and can it be fixed?
Noticed white, powdery marks or bubbling under the lacquer on your alloys? That is corrosion, and it is one of the most common problems we see, especially on older wheels and over winter. Here is what causes it, whether you need to worry, and what can be done about it.
What does alloy wheel corrosion look like?
It usually starts as dull white or grey patches, often around the rim, the valve or under the lacquer. As it spreads the lacquer can lift and bubble, and the surface underneath turns rough and pitted. You might also hear it called oxidation, and in its worse stages, pitting. Caught early it is cosmetic. Left alone it works its way under the finish and across the face of the wheel.
What causes alloy wheel corrosion?
Alloy wheels are protected by a lacquer or paint layer. Once that is breached, by a kerb scuff, a stone chip or age, moisture and road salt reach the bare metal and it starts to corrode. Winter is the worst time for it, because grit and salt on the roads speed the process up. Brake dust and harsh wheel cleaners do not help either.
Is alloy wheel corrosion dangerous?
Mild surface corrosion is a cosmetic problem, not a safety one. But left to spread it can become a safety issue: corrosion around the bead, where the tyre seals to the rim, can cause a slow puncture or a poor seal, and deep corrosion weakens the wheel. So it is worth dealing with while it is still on the surface rather than waiting.
Can corroded alloy wheels be repaired?
Yes, in most cases. Surface corrosion can be stripped back, treated and the wheel refinished so it looks as good as new. The key is catching it before it eats too far into the metal. Once corrosion has pitted deep into the alloy, more work is needed, and in severe cases a wheel may not be saveable, though that is rare. A proper refurbishment removes the old finish entirely, treats the corrosion and refinishes the whole wheel, rather than covering it over.
Can you remove alloy wheel corrosion yourself?
A light surface bloom, the early white dusting, can sometimes be cleaned back with an alloy-safe product and a bit of effort. Be realistic about the limits, though. Once corrosion is under the lacquer or has started to pit the metal, cleaning the surface will not stop it, because the problem is underneath the finish. At that point the lasting fix is to strip the wheel back, treat the corrosion and refinish it, which is a job for a specialist.
How to stop alloy wheel corrosion coming back
Keep the wheels clean, especially over winter, so salt and grit do not sit on them. Use a pH-neutral wheel cleaner rather than anything harsh. Get chips and kerb scuffs sorted before moisture gets in, since that is how most corrosion starts. And a fresh, properly cured finish is far more resistant than a tired original one.
Seeing corrosion on your alloys? Find your nearest branch for a quote.
