I could be wrong, but it could be that he was following the gps route, got a ticket for being on a road that a truck wasn't supposed to be on, and his interpretation of the story is that he got a ticket for using non truck gps. There has been several low overpass hits recently because a driver was following a non-truck gps route. I don't care if a truck specific gps says "go this way", you still can't just turn your brain off and not pay attention. As many of you have noticed, there are some real dumb people driving trucks these days.