The 'Check Brake Linings' light came on a couple of days ago in my 2002 X5. From what I've read, it's the pads & sensors that need to be replaced. The BMW dealer (Ferman BMW, Palm Harbor, FL) said that they might have to replace the rotors as well, and that it's common in X5's to have to do so. He quoted me for the front @ up to $650, and said that he'd call me if the back needed replacing too.
My X5 has about 42k miles on it - is what the dealership telling me true? He said if it's just the pads & linings, it's $200 - that's a better price

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Thanks- Stan