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I have a 2000 ex auto tansmission with a little over 120k miles on it. Engine was fully serviced (about 1.5k worth) at 100k miles. Car has always run great and never given me any problems, until now. About two days ago after getting on the highway I started to notice a scratching/grinding noise. The noise happens when the car is about to shift, and only happens at higher rpms. If you accelerate slow the noise doesn't happen, but if you rev it up and accelerate faster it does. The car still shifts just fine, no jumping or slipping. Honestly, I have no clue what it could be. I'm taking it in to get checked out thursday, but wanted to see if anyone had an idea before I do that.