Having shopped for tires just a few months ago, I got a short lesson in trailer tires. The info Catfan gave is good, I just wanted to stick my 2 cents in. With trailer tires, it's all about sidewall. A trailer tire on the front of your car would probably slide when put into a hard corner due to the lack of sidewall flex. Trailer tires are built to tolerate rough bumps, like rough railroad tracks, much more than a car tire would. I was told the sway factor is only a sometimes issue with certain trailers, like a utility trailer loaded and swaying anyway, with car tires it's magnified. Car tires will do for a short term spare, but you're better off to buy trailer tires for the trailer. Prices I found went from $35 for an import that no one could tell me where it was made, to about $120 for a good year marathon. Most folks would go for the Good Year, being American made and all, but I think your money would be better spent on a different tire. I know of 5 of these that have failed way before their time, 2 on one guys trailer. I spent $140 for a mounted pair from the local Co-op and I'm happy with them so far. Shop a lot before you buy, there's lots of info to look over. Like Catfan said, inflation is key. I check about once a month. Good luck.
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