You should make sure its not your clutch though, because as you described it that is what happens when you clutch slips. Easy test: on the hwy, put it in a high gear (4th or 5th), starting at low rpm, floor it, if you see your revs jump with no acceleration, then drop back down and then your car accelerates, your clutch is on the way out. This happened to me at ~21k miles. Problem is that it is hard to replicate without the Procede, but the dealer was still able to.
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