Trailers are different from cars.
The tires wear differently because they are loaded
differently. If you watch how they behave in a turn
you will see that they scrub intensely as they do a
turn. Come out and help set up a NASA/X and watch how
my tires behave as we drop cones on the course. There
is no Ackermann effect at all. No steering at all.
They must push and drag on every turn. It is brutal on
the concrete! This wears the edges faster than the
centers if there is a lot of tight turning done over
the useful life of the tire. It also explains why
there are special trailer tires worth the search
rather than just using car or truck tires.
They also are normally preloaded in positive caster so
as the axle deflects under load they will become zero
caster. This seems rather overdone in most cases. The
newer style rubber torsion suspension is far better in
this regard than the old fashioned steel semielliptic
springs on a beam axle. Also, the steel springs are
invariably mounted in cheap plastic bushing which wear
out in about 40,000 miles and let everything wobble
about until the shakles wear through. Bad dog. This
does weird things to the tire wear too. Nice brass
bushing kits are about $100 and include greaseable
bolts and stronger shackles, well worth the upgrade.
Another hidden or at least unsuspected cost of owning
and using a trailer, and another reason used trailers
are generally not a good value.
The most common failure mode of a trailer tire is a
puncture of the rear tire that goes unnoticed until
the tire is destroyed. The front tire kicks stuff up
and the rear tire "nails" it. Especially on an open,
lightly loaded trailer, the problem is undetected, the
forward tire more or less carries the whole load,
until parts start flying. It is much better that the
rear tire goes first. When I had a front tire go, it
took out the rear and everything peeled of and I was
on two steel rims! On the Mare island bridge going to
Sears Point. No shoulder to stop and fix things on.
Only a mile long. We sounded like a steel drum band as
we crossed that bridge at about 5mph. Everything had
been fine 3 miles before at the gas station in
Vallejo. We gots stories!!
So I doubt you are seeing a tire inflation problem. 8-)
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Dennis Hale
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