Doug.S

I have a problem C5 2004: GM chromed wheels: seem to have some course bumps or corrosion on inside of the wheel that is hard to see from outside (outside, that you can easily see, looks perfect).

How best to clean, restore, preserve?
What to use? How to do?

or simply ignore? or will be worse later?

I assume taking wheels off is only good way to get to the rough surface.

ztheusa

Send them to wheel shop.

frsr06

If they are original wheels they are not chrome - they are aluminum with a clear coat on them. What you are seeing is a degradation of the clear coat. You can fully strip them and leave them - which means you will have to buff them once or twice a year. Or - they can be re-cleared with no idea of the length of time it will last. Good luck.