Possible to have a 3500 Dually Truck as a TOAD vehicle?

Papers checked? Someone asked. Guess it don't happen to everyone but I was stopped at a checkpoint once where they checked your license and registration and made sure it all was up to date and matched. They also looked inside the trailer. I also once had a fuel sample taken from the DP to see if I was using off road fuel. You tow a conspicuous looking mess like I have and they just get curious I guess.