It's time to wash the car, but when you get to the wheels they are covered by a hard to remove gray dust. Even after you clean it off, it comes back quickly. Welcome to the world of brake dust. The good news is brake dust is completely normal and is not a symptom of failing brakes; the bad news is every time you use your brakes you create more brake dust.
What is brake dust?
The gray-black dust that often covers a vehicle’s wheels is called brake dust. Basically, brake dust is made up of iron particles and is caused by the grinding of the cast iron brake rotor by the brake pads. In addition, brake dust also contains some of the metallic elements of the brake pad and carbon residue, which also comes from the brake pad.
The majority of modern brake pads are semi-metallic. A bundle of steel fibers is compressed and then fused with other additives to build a pad. Steel fiber can actually make up 30% of the brake pad so when it is pressed against the brake rotor it scratches the rotor and creates brake dust.
It's possible to buy non-metallic brake pads, which are made with Kevlar fibers, but they are expensive so very few automakers use them as standard equipment. In the industry, these types of brake pads are referred to as organics and tests have shown that they outperform as well as outlast normal brake pads. In addition, there is a significant reduction in brake dust as well as rotor abrasion.
Why it's important to clean brake dust
While brake dust is not indicative of a malfunctioning brake system, it can be harmful to the wheels if it is never cleaned. Brake dust can corrode the clear coat and over time it will eventually eat into the aluminum alloy surface of the wheel.
Fortunately, cleaning brake dust is not that difficult and the main ingredient is elbow grease. Your local automotive shop should sell wheel cleaner, which will come in handy when dealing with brake dust. Here is what you will need:
- Wheel cleaner
- Hose and nozzle
- Soft bristle brush
- Liquid wax
How to clean brake dust
The wheels should be cool before you start.
Rinse off the entire rim off with water, which will remove grit and dirt that may scratch the wheel during the scrubbing.
Cover the rim with wheel cleaner and allow it to soak for 60 seconds. Make sure you get the cleaner into all of the nooks and crannies of the wheel as this is where dust tends to accumulate.
Use a soft bristle brush and scrub the surface of the wheel, make sure the brush gets into all of the small, recessed areas of the wheel.
Rinse off the wheel cleaner as soon as you have brushed the entire wheel. Do not leave the wheel cleaner on the wheel for any length of time.
Dry off the wheel immediately after rinsing.
Applying a coat of paste wax every few months will help protect the wheel as well as make them easier to clean the next time brake dust builds up.