When was the last time you took a really good look at the tires on your horse trailer? While air pressure is very important, it’s not the only thing that counts when it comes to tire safety.

Everything you need to know about your horse trailer tires is printed on the sidewall of the tires, and knowing what all those markings mean could prevent you from having a blowout.

Tire Size and Application—Among the largest listings on the side of the tire will be a number that starts with LT or ST, such as ST235/85R16F. The LT stands for "light truck," such as an F-150 or Chevy 3500. The ST stands for "special trailer." Both LT tires and ST tires can be used on horse trailers, however ST tires are specifically designed for use on trailers and have some decided safety advantages.

Because LT tires are made for trucks, they are engineered to provide good mileage, proper traction, and a good ride. It is the last part about the “good ride” that makes them decidedly less appropriate for use on a horse trailer. A towing vehicle (truck or car) has a sophisticated suspension with struts or shocks, torsion bars, and springs. A horse trailer has a much less sophisticated suspension. As a result, trailer tires are forced to endure much more pounding when they go down the road.

ST tires have stronger sidewalls to handle this pounding. When a towing vehicle rounds a corner, the LT tire sidewall actually permits the tire on the road to flex significantly. This isn’t a problem, as the truck has a suspension that assists to compensate for this action. However, when an LT tire is on a horse tr