[wagonman76]

Trailer tires are going to be a lot tougher than passenger car tires. They have a very stiff sidewall to handle a lot of weight. Typical 5 lug trailer axle is rated for 3500 lbs. Thatd be like a 7000 lb car. Plus trailers typically dont have shocks so the tires are made to really take a beating. My 900 lb (empty) utility trailer had almost no air pressure in its 14" tires for quite some time, and I never knew it because the sidewalls retained their shape anyway.