Aluminum is not the hardiest of metals. It is really often there just to look good. But, because of its susceptibility to fading and oxidization, you will have to work at it to maintain those shiny wheels. Every now and then, you will have to give them some extra care.
For most of your cleaning, you can use an acid-free aluminum cleaner. You don’t want to clean aluminum wheels with just any cleaner. But, eventually you will need to use an acid wash.
An acid wash, also called an oxidized wash or aluminum brightener, can remove even heavy oxidization on aluminum wheels. The important thing is to make sure it is a product that is specifically designed to remove oxidization from aluminum car parts and restore their shine.
Make sure that you are wearing some good latex gloves and safety goggles whenever you work with acid wash. You must protect your skin and (especially) your eyes from this chemical product. You should also keep first aid supplies handy, just in case.
Depending upon the severity of the oxidization, you will need different levels of concentration of the cleaner. For example, with regular strength aluminum brighteners, you will generally dilute it to a 1:50 ratio with water. If you have a lot of oxidation, you will need a higher brightener to water ratio.
Now, while it is important to remove heavier oxidization from your aluminum wheels, you don’t want to do this too often. A small amount of oxidization actually protects the aluminum from corrosion and more rapid damage.
Only use the acid wash when you can really tell that the oxidization has gotten to that point. The need to allow some slight oxidization for protecting the aluminum is also the reason why you need to use acid-free aluminum cleaners, in-between acid washes. Remember that the goal is to preserve the life and luster of your aluminum wheels, but using acid washes too frequently can actually do more harm than good.