Towing stability studies
Not so simple actually. There are other variables than hitch weight:
1. A glider trailer with a foil-shaped dog house.
2. Independant suspension with variable geometry as seen on many
smaller tow vehicles. This matters
a great deal if the rear suspension compresses unevenly or
rebounds unpredictably after bottoming.
3. The weight distribution of the tow vehicle itself.
4. The distance from the tow ball to the rear axle of the tow
vehicle AND the trailer.
5. How well side to side motion of the tow vehicle rear axle is
limited.
. 6. Side-wall stiffness of the tires.
I could go on. Even if the trailer weight on the hitch is proper at
rest, it may change radically over bumps, under cornering loads or
during heavy acceleration or braking,especially if there's a lot of
weight at the ends of a long trailer (think spare tire, rigging stuff,
tools, etc.) A trailer which is well behaved with no traffic may do
strange things when passing a line of tractor-trailers. Unequal side-
to-side tire inflation ON ANY AXLE OF THE COMBINATION can provide real
adventure.
Some suggestions:
Don't load the hitch anywhere near the tow vehicle weight limit.
You want to set things up so 7-10% of the trailer weight is on the
hitch and the suspension doesn't bottom when you bounce on it. If the
standard suspension bottoms, add helpers. Add aftermarket sway bars
if the rear suspension allows side to side movement.
Check your tire pressures often, at least every fuel stop. While
you're at it, touch the bearing caps with the BACK of your hand to
check for overheating.
Good tires and shock absorbers are still cheap compared to gliders and
trailers.
A good place to work out the kinks is a big empty parking lot on a
weekend. Accelerate in a straight line, tug the steering wheel
sharply to one side or the other and release it. Start slowly and
increase speed in small increments.
If you can stand the size and poor gas milage, it's hard to go wrong
with a pickup or commercial van with a solid axle and a factory tow
package, BTW
My suggestions/opinions only; your milage may vary.
Ray Warshaw
1LK
There's not a whole lot there, but that reflects the fact that
stability is pretty simple: have at least 7% of the trailer weight on
the hitch (up to the towcar's limit), and concentrate mass low down
around the axle.
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