Coupling To The Tow Vehicle Tongue Weight as a Percentage of Loaded Trailer Weight Type of Hitch Percentage Ball Hitch (or Bumper Hitch) 78 10–15% for large trailers 6-10% for smaller utility trailers Gooseneck 20–25% ! WARNING Improper tongue weight (load distribution) can result in loss of control of the trailer, leading to death or serious injury. Make certain that tongue weight is within the allowable range. Be sure to: Distribute the load front-to-rear to provide proper tongue weight (see chart); Distribute the load evenly, right and left, to avoid tire overload; and Keep the center of gravity low. CHECKING TONGUE WEIGHT To check the tongue weight, the tow vehicle and trailer must be on level ground, as they will be when the trailer is being towed. Take the trailer to a truck stop or grain elevator where there is a “certified” scale. Place the tow vehicle only onto the scale and get the weight. This weight must be less than your tow vehicle’s GVWR. Pull the trailer onto the scale and uncouple it from the tow vehicle, leaving just the trailer on the scale. Get a ticket which lists the total trailer weight. Re-connect the trailer to your tow vehicle and the drive the tow vehicle wheels off the scale, just leaving the trailer axles on the scale. Get a “ticket”, which lists the trailer’s axle weight. Simply subtract the axle weight from the total weight to determine the hitch weight. While you are at the scale, you should weigh the entire combination vehicle. This result should be less than the Gross Combined Weight Rating (GCWR) for your towing vehicle. Some scales allow you to get individual axle weights also. If this is possible, get the tow vehicles front and rear axle weights to make sure they are in the same proportion as the tow vehicle alone, and that the rear axle is not overloaded. This is the best way to check that a weight distribution (or loadleveling) hitch is adjusted properly, i.e., you have the proper number of chain links attached to the snap-up brackets.
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