I was looking online at the different types of rotors available, and I saw two that were in my "price range". Though they looked the same, I used the websites compare feature, and they spec out exactly the same, except for the brake rotor diameter. One is listed as 11.17", and the other measures 10.31". I have been having issues with the rears ever since I had my brother in law work on them about a year ago. The rotors were replaced in his endeavor. Could he possible have used the wrong size rotor? The other thought on this is, why are there 2 different sizes? Are the front and rear diameters different? I will be replacing the rears and need to make sure I am getting the right one. Any help is certainly appreciated.