How To Remove Oxidation From Aluminum

Oxidation occurs when metals are exposed to oxidizing agents. When this happens, especially aluminum, the metal forms a thin but hard aluminum oxide film. So what should you do if you want to remove oxidation from aluminum?

1. Check the coating

Some aluminum wheels have a clear coat on the aluminum to protect the metal and prevent oxidation. You need to determine if you have the coating. Using a clean microfiber cloth, apply a small amount of polish to a small, invisible area. When you wipe off the polish, the aluminum oxide will leave a black residue on the rag, which means you have bare aluminum. If there is no black residue, then you have a coating. If you have a coating, you probably just have dirty rims and not oxidation. Follow the cleaning steps below. If it looks like you still have oxidation and the coating is out of shape after cleaning, you may need to remove the coating with paint thinner before proceeding to step 3.

2. Clean the wheels

Assuming you don't want to remove the wheels to get the job done, park your car in a shady spot away from dust or grime. Removing the wheels will make the job easier, but this requires lifting your car and removing all the wheels or two at a time. Start by removing loose debris, dust, dirt and grime from the wheels. Your wheels may have brake dust, road grime, and caked-on grime, which should be removed first. A stainless steel wire brush can help remove some stubborn dirt. Using a hose with a nozzle, wash the wheels with water. Work slowly, cleaning one wheel at a time to remove any loose buildup along the way. An optional but recommended step is to give it a deeper cleaning with an aluminum wheel cleaner.

3. Grinding the rim

Begin with 400 grit wet/dry sandpaper and sand the rims to remove any pitting, scratches and curb rash.

If there are deeper pits or scratches, you may want to start with a more aggressive sandpaper, such as 240 or 320 grit. Sand until all pitting and scratches are gone. Then switch to finer-grit sandpaper and sand the surface until you reach 800 or 1,000 grit to remove any grooves or roughness. Then use a clean, dry microfiber cloth to wipe away sanding dust.

4. Rinse and dry

Hose again to flush all soap and detergent from the wheels, tires and wheel wells. Clean these areas thoroughly, making sure to get in between the nuts and spokes. Dry the rim with a clean, dry microfiber cloth. Do not let them air dry as this will cause spots.

5. Polishing

Use your favorite compound to polish your now clean and oxidation-free wheels. Polish with a dry microfiber cloth, felt polishing disc, or ball power polisher.