I had the grind when shifting into 4th and 5th at high rpm. After the switch it was immediately fixed and has been ever since. Good luck.
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90 300zx TT 13.395@105.55 94 Camaro Z28 13.775@101.83 03 WRX 13.973@94.88 99 Ford Windstar; four kids and wife don't fit in the Z. 90 240sx (sold) 16.9@87