I have a 1990 Ocean Yachts 48' MY with a rattle over 1500 rpm at the stern/rudder area which is also on the port side. My boat is currently hauled at Lamb's Yacht Center in Jacksonville FL. They were not able to track down the rattle and are guessing it is the trim tab. I don't believe that is the problem. The trim tab is just a thin sheet riveted to the hull with a hydraulic piston that moves it 3" max, and I don't use it on the port side because the boat lists to the port. My question if I remove that tab altogether (to eliminate that possible rattle source) and leave the starboard one how would that effect the boat running underway? The reason I am considering it is that I plan on installing the Zipwake system and I feel the current system is almost useless.