The Semi-gloss black roof rails on my 2007 325D M Sport Touring are really quite badly faded and the paint seems incredibly thin. You only need to wipe it with a leather after washing & more seems to wipe/scratch off . Does anyone have any good ideas to re-black them without repainting? Waxing improves in the very short-term. Don't know if black wax would help or maybe even shoe-polish! Mine can't be the only one with this issue - can it?