Originally Posted by THE TECH
While the PS21 gel works decently, I don't agree that it will prevent rust on the rotors. It lessens it some but definitely does not prevent it.
Seeing as how the rotors get rusty after a hard rain (car sitting) I don't see how the shampoo affects this at all. Seems like just water will rust the rotors.
This is my biggest peeve when/following washing. My newly cleaned wheels get trashed with orange "dust" and I have to clean them again- that's why I don't even bother drying my wheels with the rest of the car since I'm jut going to clean them after the first post-wash drive anyway....