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A Product of Progress Mfg. Inc.
Appendix B - Weight Distribution Adjustments
Study the following concepts and their effects on your vehicles when setting up your
hitch for the first time, and when adjusting your hitch before each trip:
Tow vehicle rear axle to hitch ball distance
: A longer distance will transfer less
weight distribution than a shorter distance, with the same spacer 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 give way easily with very little weight applied, then later allow
less movement, even with a significant change in applied weight.
Trailer axle to coupler distance
: Trailers with longer distance will try to force
distributed weight forward to the tow vehicle before absorbing it into the trailer
suspension. Trailers with shorter distance 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 makes the trailer more stable and helps provide the
movement resisting friction on the L-brackets, and therefore the resistance to 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 gross trailer weight. Always follow the trailer manufacturer’s guidelines for
tongue weight. A tongue weight that is too light will make the trailer more likely to
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 fresh water and/or full propane tanks that are tongue weight when
you leave can empty and become full waste tanks that subtract tongue weight for the
return trip. Shifting 40 gallons of water from the front to the back of your trailer can
change 330 lb of positive tongue weight to 330 lb of negative tongue weight.
Rear-load toy haulers are designed to have a heavier dry (empty) tongue weight so
when they are loaded with toys they become a more balanced load.
Front-load toy haulers are exactly the opposite. They have heavier tongue weight
with toys loaded and lighter tongue weight without toys. Be careful not to exceed
receiver hitch and tow vehicle rear axle ratings when towing with a front-load toy
hauler.
All toy haulers may require significant changes to weight distribution setups between
towing loaded and towing unloaded.