Gear Grinding Noise

I have 5700 miles on my GT500.. yesterday I was shifting at high RPMs (5800 to 6000) and I experienced second and third gears grinding severely. I am not sure if it is the shifter or the clutch. I plan to call the dealer but was wondering if anyone had experienced this. It does not do it in low RPMs.

Thanks for comments!

Update

Just for anyone else's information - I returned to the dealer and they both heard and felt the noise but the result was "we haven't have THAT many complaints and you still have plenty of warranty left". A week later I receive a form they wanted me to sign stating they found NOTHING wrong.

I wrote the Executive office of Ford Motor Company saying basically that if they have one complaint or 50, it should not matter. It should be fixed. Almost immediately I received a reply - they wanted me to power shift another shelby at another dealer, but the dealer (and I can't blame them) did not want to let me do it. However, the service department at this dealership did recognize the problem once they drove it and diagnosed it as two synchronizers in the transmission had gone bad. They also said for what the car cost they would not repair it, but were going to replace the transmission completely.

I'm disapointed in the original dealership's handling of the situation, but am thankful that Ford Motor Company took my complaint seriously.

Now if only I can convince the dealership to give me the other Shelby on loaner while they fix mine....