I had the same problem on my 2000 I bought new. I don't remember exactly what it was, it was something in the tranny was not right out of the factory when we tore the engine down, but I was tearing it down to sell the engine in pieces. Mike at SAE took it apart and found the issue while we were, so if he is on here and can reply, he may remember the problem. I cannot remember it since it was a few years ago.