How to Restore and Protect Milky Anodised Trim

If you own an Audi, Mercedes or a BMW , you may have noticed your once-shiny silver trim turning cloudy or milky over time. This is a common issue, especially on anodised aluminium used in modern car trims. The good news is – it can be fixed and even prevented.

What Causes the Milky Look?

Anodising is a process where a protective aluminium oxide layer is bonded to the metal. It adds durability and a satin-like finish, but it’s vulnerable to strong alkaline cleaners, heat, and poor rinsing. These factors can break down the layer and lead to oxidation, which appears as a chalky, streaky, or milky residue on the trim.

The problem isn’t usually mineral deposits or water spots – it’s chemical damage, often caused by wheel cleaners, degreasers, or soap residue left to dry in the sun.

How to Fix It

To restore the trim:

Use a metal polish to gently remove the oxidised layer and bring back the original finish.
Polishing compounds can also be effective when applied with care.

 
Avoid alkaline cleaners, as they can worsen the staining.
Mild acids or fillers may clean or hide the damage temporarily but don’t offer a long-term solution.
Sanding may work in severe cases but risks permanently damaging the anodised surface.

Can You Over-Polish?

The anodised layer is tough, but with repeated aggressive polishing, it can eventually wear away. Light, occasional polishing is generally safe and effective – the key is to avoid overdoing it.

How to Protect the Finish

Once the trim is restored, protecting it will help prevent the issue from returning. Ceramic coatings offer moderate protection against chemical exposure but may not hold up under harsh conditions. For maximum durability, Paint Protection Film (PPF) is the most reliable option, creating a physical barrier against UV and chemical attack.

If you’re looking for long-term peace of mind, ceramic coatings can be a convenient solution, but PPF offers the strongest defense.
For a quick and easy protection we would recomend our Ceramic Spray Sealant Hercules

Maintenance Tips

• Avoid using strong alkaline cleaners.

• Rinse thoroughly after washing.

• Avoid working on the trim in hot weather.

• Maintain the finish with a light polish every few months, if needed.

Extra Consideration

Polishing and protecting trim while it’s still mounted on the vehicle can be challenging. In some models, especially older convertibles, removing the trim requires dealing with rivets and fragile clips – which adds time, effort, and potential cost. Consider this before starting the job.

Conclusion:
Milky anodised trim doesn’t have to be permanent. With the right approach, it can be restored and protected – keeping your car looking sharp for years to come.