My old trailer had mobile home axels under it and I found some like new tires off a mobile home and I asked the DOT trooper if I could use them. He looked at them and he showed me a stamp on them that said DOT and some numbers so he said they were legal. he also said that if he pull over a mobile home and there is no DOT stamp on the tire nothing moves till the correct tires are on there. This is Wisconsin so your mileage may differ. Also the mobil home tire that I had were 8 ply.