I bought a used 2008 WRX (not from a Subaru dealer) a couple months ago with about 85k KM.
Last week, the car started making a grinding noise at ~2000-2500 RPM when I let off the gas in first or second gear. The grinding noise only appears after ~1 hour of driving and it's much worse when it's warm outside. The car drives fine, it's just doing an really horrible noise.
I went to a dealer to have it checked and the technician that took the car for a test drive said that I might need a new transmission. From what I understand, this should be covered under the power train warranty but the dealer said that without proof that the scheduled maintenance were done they would not cover it.
Long story short, I found where the car was originally purchased and they faxed me the service record of the car. All the scheduled maintenance were done, but some were done as much as 3500km late. Is this a big problem? Could they refuse my claim because of this?