The coupler on a trailer connects to a ball hitch on the towing vehicle. A frame-mounted hitch on the towing vehicle is better than a bumper-mounted hitch. If you are using a bumper-mounted hitch, do not exceed the weight rating of the bumper.
Make sure the size stamped on the ball hitch on the towing vehicle is the same size that is stamped on the trailer’s coupler. If the ball hitch is too small, a bump in the road could cause the coupler to lift off the hitch.
“Tongue weight” is the amount of the loaded trailer’s weight that presses down on the towing hitch. The tongue weight should be about 10% of the combined weight of the vessel and trailer (“gross trailer weight” or GTW). If the tongue weight is too light, the trailer will tend to swing from side-to-side (or “fishtail”). If the tongue weight is too heavy, the rear wheels of the towing vehicle will be weighted down, making it difficult to steer.