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 Hello
Andy:
I read with interest your recent column on how to set up
an equalizing hitch. My question is what do you do to set
up a unit that does not have one. Last fall we purchased
a 10' hardtop to tow behind our Ô98 Ford Explorer. Just
south of Denver on the interstate I was changing lanes and
it started to sway a bit. As I tried to correct it the action
became more and more violent until I gave up and put the
brakes on. The whole unit spun around on the highway and
came to a stop. Luckily there was no damage other than a
small dent in the bumper and a blown tire on the trailer.
I must confess I was doing 70 Mph at the time and we continued
on our trip never going over 60 and had no more problems
but I am nervous about towing it again.
Was what happened just a fluke that will not likely
happen again or did I do something wrong? Why did the action
continue to build? I would appreciate any reassurance you
can give me.
Hi Bill
Your letter raises several questions and I will try and
answer them the best that I can.
In theory what causes a swaying action to build is that
the trailer is actually traveling faster than the tow vehicle
so it has to take a longer route down the road and if nothing
absorbs the extra energy built up the sway will continue.
If something gives the trailer more speed the sway will
increase.
Several years ago we took an old inexpensive trailer, connected
it to an old car (read expendable) took it to the drag strip
and tried to recreate an uncontrolled sway situation. It
was a great learning experience and this is what we discovered.
1) With the sway controls in place and the equalizing hitch
properly set it was virtually impossible to get the unit
to sway uncontrollably. Even with maneuvers so violent as
to squeal the tires it would pretty much follow in line
with the car.
2) Removing the sway controls and being as little as one
link out of adjustment on the torsion bars made it considerably
less stable feeling but still possible to drive aggressively
if careful. In this state though, if you whipped the wheel
back at the wrong time it could set up a sway condition.
Here is where it gets interesting. When the sway started
the natural reaction was to try and correct it by steering
it out but this only made it worse and we had to use the
brake control to snap it straight. Eventually we discovered
that resisting the temptation to steer it out and just holding
the wheel straight would allow one or two more swings of
the trailer and then it would settle down. We tried this
several times and it worked on each occasion but I won't
say it was easy it took every bit of self control one could
muster to just hold that wheel straight.
I think especially those of us that live in Canadian winters
have natural reaction to steer with a skid from years of
winter driving. When that sway starts it has a similar feel
to the back of the car sliding and our natural reaction
is to steer out of it, after all just holding the wheel
straight will cause a car that has started sliding on ice
to begin a 180-degree spin. Unfortunately trying to steer
out of a sway causes it to increase instead of decrease
so the correct reaction is exactly opposite to what our
senses are telling us to do. (Top)
3) The best way to straighten out a sway is to apply the
trailer brakes only, and the worst thing to do is touch
the car brake. Again, it is not an easy thing to do - to
take your hand off the wheel and hit the brake control.
There are companies that make a steering wheel mounted brake
control that is easier to access. The first answer though
is to have a properly set-up and balanced hitch system so
that sway cannot easily start.
I almost learnt this lesson the hard way. About a year
after we did this at the track, we had a small 22' Argosy
that had to be delivered to the paint shop. Since it was
only 5 kilometers and I was going to take it myself and
it was only a 22' I just dropped it on the ball on our pickup.
The front sofa had been removed for upholstery while the
unit was being painted, there was no battery in it and the
LP tanks had been removed. Bottom line was that there was
very little hitch weight. To make matters worse, the 7-way
plug had been taken off for the paint job and two wires
were connected for signals.
I went around a curve in the road and that 3000 lb. Argosy
started pushing a 6000 lb. pickup around like it was a toy.
So much for the old tale "the tow vehicle has to be heavier".
I grabbed the brake control and nothing happened, so again
with a determined effort I held the wheel straight and the
trailer straightened out after a couple of swings. I don't
know if I would have done that if I had not had the practice
on the track the year before, but then again, if I had not
been so lazy and had taken the two minutes to throw on a
sway bar and torsion bars, it would never have happened
in the first place.
Having said all this, I would not be nervous about continuing
to tow your hardtop. Make sure it has at least 300 lbs of
hitch weight and I would invest in a light equalizing hitch
and a friction sway control. I cannot overemphasize the
difference a properly adjusted equalizing hitch makes even
on a hardtop, in fact same tow vehicle/trailer combinations
tow smoother than the vehicle rides on its own. There are
other enhancements you could make to the Explorer such as
a better tire size and better shocks but the greatest improvement
will come with the correct hitch.
At one time many of the brands of hardtop warned against
using an equalizing hitch because it could possibly cause
bending of the "A" Frame. I have put light 400 lb. equalizing
hitches on most of these brands without a problem. The reasoning
we used was that it was better to have to strengthen the
frame if it became a problem rather than be unstable on
the road. We never actually had one bend. Not every Hardtop
has to have an equalizing hitch, if the tow vehicle has
good stability then a weight carrying hitch with a sway
control is fine. Have a great trip this summer. (Page
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