Caring For Wheels And Tires

Rims and tyres are subject to contamination by brake dust and road grime on a continual basis and are probably the hardest part of your car to maintain to a high standard. In this guide, find out how to wash and clean alloy rims and wheel covers, how to remove stubborn accumulations of brake dust safely and effectively, how to clean and protect tyres, and how to apply sealant protection to alloy rims and wheel covers and prevent corrosion from setting in and causing permanent damage ...

Brake Dust - The Bane of Car Care Enthusiasts

Your wheels are probably the hardest part of your car to safely clean and protect, as they are subject to continuous contamination by brake dust and road grime. Brake dust is a major problem for owners of cars with alloy wheels, as it is corrosive, unsightly and difficult to remove. Brake dust is the product of friction between brake discs and brake pads. When braking, the surface of brake pads is worn way, producing dust that is deposited on other surfaces nearby, i.e. your rims. The compounds used to make brake pads vary greatly in hardness and metal content, meaning that the amount of brake dust generated can vary significantly between cars.

Brake dust is actually a combination of carbon fibres, metal filings and adhesive residues. It is often deposited on rims at very high temperatures, meaning that it immediately etches into any protective coatings. The adhesive residues in brake dust not only cause it to firmly bond to everything it touches, but also initiate corrosion in their own right, as they are often acidic. If that wasn't bad enough, the metal filings contained in brake dust have a tendency to oxidise, and if they do this when in contact with the metal of the rim the process of galvanic corrosion sets in. Thus, brake dust gradually erodes protective coatings until they fail, after which point the rim itself starts to corrode. This gradual erosion not only makes the rim look unsightly, but can also eventually affect the structural integrity of the wheel.

There are three ways to control brake dust. The first is to fit aftermarket low dust brake pads. Both kevlar-based compounds and high metal content compounds are effective in this respect. The second option is to fit dust shields, which can now be bought for most types of cars. These sit between the rim and the hub and shield the rim from the caliper assembly whilst still allowing ventilation. The downside of such devices is that they look unsightly and aren't suitable for performance cars where high levels of ventilation are required. The third option is to establish a proper wheel care routine. An easy thing to say, but what does this actually mean? In our experience, if you want to keep your wheels in perfect condition, it means a minimum of weekly washing and quarterly reapplication of a wheel sealant. Anything less and corrosion will occur, as we have found to our own cost in the past.

Regular washing should be the easy bit, but is often overlooked, particularly during the winter months when cold and wet weather often means that weekends are spent indoors and the notion of going outside to wash the car seems pointless. Believe us, it isn't. Get your coat and hat on and give your wheels a quick wash and don't worry about drying everything off; just make sure you get any road salt and brake dust off. It only takes a few weeks for serious etching to set in on unprotected rims and in the winter many weekends can pass by without a nice day. Once etching sets in you're facing a problem a bit like rust; no matter what you do it persistently gets worse.