Recently replaced the aluminum prop on my 2005 60 hp Mercury big foot four stroke engine with the same size stainless steel prop. The problem is when I shift it into gear (fwd. or rev.) I feel a slight vibration that I didnt have with the aluminum prop. It goes away as soon as the motor starts to spool up and is fine at any other speed.......its just the inital putting it in gear that I dont like. The stainless prop I bought is made by Power Tech. Any ideas ???