Also generally "Highway" tires put more rubber on the road.
Tread grooves on highway tires are for letting water out from between the tire
and the pavement, not for "gripping" the road.
Tread grooves and lugs on "Off Road" tires are for biting into the soft surface
of dirt, gravel and mud.
"All Weather" tires are a compromise between "Highway" and "Off Road" tread so
that a mainly "Highway" tire can deal with some soft surface like dirt, mud and
snow.
The quietest, longest lasting and best adhering tires on hard surfaces are the
"Highway" tread designs, assuming similar rubber compounding and casing
construction.
Since almost all of my miles are on hard surfaced roads I want "Highway" tires.
On the rare occasion that I am on non-hard surface roads I go slowly, which is
what anyone should do when towing a trailer on soft surface roads anyway.
If I get stuck traveling on slush, snow or ice I would rather chain up rather
than depending on compromise tires. Or, better yet, wait until the road is clear.
I have towed a heavy (4,600# empty) 3-axle trailer carrying a 1,400# mare and
400# colt on ice in the Cascades (got caught in a storm) with a 4WD Ford PU. No
fun at all!!!! Purple knuckles!! As soon as I could find a place to turn around
I did so and went back down, then traveled south to a clear pass. No way I wanted
to push onward even if I had had "All Weather" or even studded tires.
On rubber compounding: Expensive tires like Michelin and Pirelli (there are
others) upper grades have rubber that combines dry road and wet road traction
with long life. Cheap tires are either hard rubber for long life or soft rubber
for good traction with short tread life. Plus, the cheap tire does not have a
well engineered tread pattern.
The extra $300 or $400 for the high grade tires gets you longer life, better wet
and dry road traction, and, most importantly, less risk of a crash, that is, if
one does not use up the safety margin with excessive speeds for the conditions.
One accident less in a lifetime will pay for better tires, and may save someone's
life.
Al Grayson