Trailer Tongue Weight is the amount of weight pressing down on the tow vehicle hitch. To measure trailer tongue weight, place the tongue of the trailer on a scale when the trailer is not attached to the vehicle. Too much tongue weight can press the tow vehicle down in back, causing the front wheels to lift to the point where traction, steering response and braking are severely decreased. Suspension or drivetrain damage can result. Too little tongue weight can reduce rear-wheel traction and cause instability, swaying or jackknifing. For bumper-pull and receiver-style hitches, to insure proper handling, keep the trailer tongue load between 10%–15% of the actual trailer weight, within the limits of the maximum trailer tongue weight allowable. For example, for a 2,500-pound trailer, multiply the weight of 2,500 pounds by 10% to arrive at a figure of 250 pounds If using a 5th-wheel or gooseneck trailer, tongue weight should be approximately 20–25% of trailer weight.