Pick up trucks PULLING a 5th are OK, the problem is pick up trucks with a camper shell on the bed.
Since a camper shell is not permanently attached to the truck and can be dropped on the ground, it is considered cargo and theoretically can not have a TIP, key word in Spanish is "casa RODANTE", litteral translation is "rolling home" and not recreational vehicle "vehiculo recreativo'", or motor home "casa motorizada".
Sometimes Mexican Government officials can get very sticky with wording when it comes to documents, simple words can complicate and mess a "tramite", since the TIP's do not specify what a motor home really is they might be looking at the wheight of the pick up truck as a cargo carring unit, as opposed to a tractor pulling a trailer that is a home, of course class A and C units and B's are self propelled, pick up's whith a bed carring a box is another matter, for them a box is a box whether it carries cargo or living quarters is irrelevant, the pick up truck is a cargo carring vehicle and subject to commerce rules and import laws.
navegator