How's the RPM's? When the boat is pulling are the RPM the same. I have to tweak my throttle a bit to get both engines running at the same rpm. I suppose I could make some adjustments on the throttle cable to minimize this. If it isn't the throttle cables then I'd take a good look at the props. I'd only doo this after checking all the nuts and bolts in the steering. Lost a bolt on one of the steering cone once. It wasn't difficult to fix, but it ended my day early since I didn't carry a replacement bolt.