Hi My Accord is in for it's annual service, and I had a call to say one of the rear brake piston (?) is corroded and needs to be replaced, along with a "O" ring. My car is very late 2007, with about 47k miles. Is this normal, or I am just unlucky? Dealer quoted me £210.00 to replace etc. I don't remember ever having to do this on any Disk braked car in the past!