I read about this sometime back: A guy who had bought a nice car for less at an auction in US drove across the border and was re-entering from Mexico. I think a customs dog smelled the tires, he was stopped, the car was stripped and for reasons I don't remember, he ended up in Mexican jail. Pretty horrible experience for an innocent guy; of course he lost his car too, since it became 'evidence' (and was probably pretty badly cut up anyway).
