Europe's famous automakers don't always agree on everything but they do think alike when it comes to wheel care. BMW, Mercedes, Porsche, Audi, VW and Volvo all use and recommend P21S Wheel Cleaners to remove brake dust and road grime from their alloy wheels.
Developed in 1976 by a German chemist, P21S is a safe, pH-controlled, non-acid, non-lye based detergent that provides terrific cleaning and guarantees not to damage any type of wheel: painted, clear-coated, polished or anodized.
While more costly than the wheel cleaners found in discount and auto parts stores, P21S Wheel Cleaners can be significantly cheaper to use over the long run... ask Porsche owners who ruined their 911 5-spoke forged alloy wheels using the wrong wheel cleaner!
Gel Formula P21S - for wheels that tend to soil heavily due to higher braking speeds, softer brake pads or infrequent cleaning. Spray on, allow to stand up to two hours, lightly brush or sponge the surface and rinse off with a sharp stream of water. Gel composition clings to vertical surfaces to provide increased cleaning effect.
Wheel cleaning: Brake dust can cause permanent damage to the surface of your rims, so you should never forget the wheels when washing. Thorough and regular care of your wheels will add the finishing touch to your automobile.
P21s was absolutely what my old wheels needed. So clean!!
I had gotten busy, and let the cleaning regimen of my M3 lapse. As a result, my wheels were filthy with brake dust and road grit. Washing with mild car wash soap (as normal) using various brushes, etc. just didn't get rid of the built up grunge. Ordered some P21S (as I heard it was safe), and wow, great results. Spray on, wait a few minutes, wash down, wipe down and they were clean again. Great stuff.
I've used this gel on many different wheels all in different needs of cleaning. P21S has been great for baked on brake dust and has a long cleaning time once applied. It is a little expensive for maintenance washes so I usually reach for this stuff when I'm facing some neglected wheels. Highly recommended.
Owner Killer B Motorsport
We've tried nearly every wheel cleaning product over the years and recently decided to try P21S. By far the best product we've ever used! Melts brake dust and does not damage wheels. Great stuff!
effective and gentle
A little goes a long way. It cleans well but is gentle enough to be sprayed and left on for hours. In conjunction with a good brush it will be keep your wheels nice and clean. Does not appear to have negative effect on wheel wax/sealant either.