Appendix B – Weight Distribution Adjustments

You should carefully consider the following items and their effects when setting up initially and when adjusting your hitch before each trip:

  • Rear Axle to Hitch Ball Distance: A longer distance here will transfer less weight distribution than a shorter distance with the same washer and L-bracket settings.
  • Vehicle Suspension: Soft suspensions, such as an SUV will react farther and faster to weight distribution adjustments than stiff suspensions like a 3/4 ton pickup. For a smoother ride, some vehicle suspensions are designed to be very soft with the first few pounds of payload, and to then stiffen as the load increases. This means that initially the springs move a long way with very little weight applied, then later move much less, even with a significant change in applied weight.
  • Trailer Axle to Coupler Distance: Trailers with longer distances will try to force distributed weight forward to the tow vehicle before absorbing it into the trailer suspension. Trailers with shorter distances absorb more of the distributed weight into their own suspensions.
  • Tongue weight: To operate effectively, your tongue weight should be at least 10% of the gross trailer weight. This helps provide the sway resisting friction force on the L-brackets and head sockets of the hitch that give it the ability to resist movement and thus to resist trailer sway.
  • Trailer loading: This is one of the most significant factors that influences trailer sway. Most trailers are designed to have a tongue weight of between 10% and 15% of the overall trailer weight. Always follow the trailer manufacturer’s guidelines for tongue weight. Trailers that are “back-end heavy” can often cause trailer sway. Trailer loading changes tongue weight dramatically, and loading can change dramatically from one trip to the next, or even during the course of a short weekend trip.

For example; full water fresh tanks that are tongue weight when you leave can empty and become full waste tanks that subtract tongue weight for the return trip. Shifting just 40 gallons of water from the front to the back of your trailer can change 330 lbs. of positive tongue weight to 330 lbs. of negative tongue weight.

Rear-load toy haulers are designed to have very heavy dry (empty) tongue weights so that when they are loaded with toys they become a more balanced load.

Front-load toy haulers are exactly the opposite. They have much lighter tongue weights without toys, and then can get very heavy when toys are loaded. You must be careful not to exceed receiver hitch and tow vehicle rear axle ratings when towing a front-load toy hauler. All toy haulers may require significant changes to weight distribution setups between towing loaded and towing unloaded.

Cargo carriers, bike racks, and second trailers attached to the rear bumper of a trailer add weight to the rear of the trailer that automatically subtracts tongue weight. We recommend that you do not add weight of any form to the rear bumper of your trailer. We also recommend that you do not tow a 2nd trailer under any circumstance.

  • Trailer coupled attitude: Attitude or pitch refers to the angle that the trailer is tipped to. It is generally accepted that a trailer should be towed sitting parallel to the ground, or with the front (coupler) tipped slightly down. The front tipped too far up or down may be an indication of improper trailer loading, or a need to adjust the ball height or weight distribution settings.
  • Vehicle weight ratings: Each trailer and tow vehicle has a maximum Gross Vehicle Weight Rating (GVWR). The tow vehicle and towing equipment, including receiver, shank, hitch, and hitch ball all have maximum weight ratings for tongue weight and trailer weight. Tow vehicle and trailer also have maximum axle weight ratings. NEVER exceed any of these ratings.