For those of you travelling down with a Truck/Camper, this is what happened to us when crossing at Nogales on Nov 20th. It was a holiday in Mexico….significant I think. We are Canadian. We obtained our permit at the Banjercito at km21, in the routine we had expected and were familiar with. As we were about to leave we were approached by an official in the parking lot who told us that we had to go back to the windows with photos of our rig. We were told that our 3500HD truck was too heavy and that we had to wait for special permission before proceeding. They took back our permit we had already paid for. We were told that they had to send the pics off and that it would take about an hour….this was at 9am. We assumed the pictures were going off to some distant office. At about 10:30am our anxious enquiry was met with an assurance that permission would surely be forthcoming in 20 mins to one hour more. At 12:15pm we told the official that we wanted our 8000pesos returned. He went over to the Aduana office across the courtyard and spoke to the guy there, whom we had not really seen until then…..he seemed to have been hiding behind a closed window during most of our long wait. Was this the person whose decision we had been waiting for…..just across the courtyard, and for over three hours ? Quite a revelation ! Banjercito guy came back and said that we had been denied entry. Something to do with being a work truck and commercial vehicle. We obtained a refund and went back north; we returned to the USA.. We drove over to the crossing at Lukeville, south of Ajo. On Wednesday 22nd we re-entered Mexico, drove the 20 odd kms to the Banjercito there, and were issued a permit with no problems. It also cost a little less than the former one surprisingly ! We used the word 'motorhome'. Also providing a destination closer to the border may be significant. They seem to be concerned about about people bringing goods over to sell. Don't really know….but this sort of thing seems to be happening to others also. If this is you, be prepared, and persistent !