Car Clinic: Why have my alloy wheels turned black?

Q. The alloy wheels on our 2014 Ford B-Max turned from silver to black shortly after purchase. Why?
TS, London

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A. The cause is almost certainly brake dust on the wheels. When the brake pads press on the moving discs, a thin layer of the pads is rubbed off in the form of a fine dust, which then sticks to the wheels. Rain or damp mixes with the dust to create an inky stain. It won’t do any harm, but it does make wheels look dirty, and the longer it’s left, the more difficult it is to remove.

Try a cleaner such as Bilt-Hamber Auto-Wheel (£12.85, theultimatefinish.co.uk), which is neutral in pH so won’t attack the protective lacquer. Then apply a protectant such as Collinite No 845 Insulator Wax (£22.95, theultimatefinish.co.uk) or Armor All Shield for Wheels (£7.99, halfords.com). Clean and reapply occasionally.

INSPECTOR GADGET
Dave Pollard has written several Haynes manuals and has tested just about every car-related accessory — read more from Dave here.

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