Crossing back into the U.S.

Paul.. We just returned from La Penita and crossed at Columbia on Sunday afternoon. We were driving a Class A motorhome plus a towed vehicle. We were directed to the truck lanes and told to go to lane 4 or 5. (the farthest right ones) There was no inspection such as questions about the kind of food we're bringing back or other items we purchased while in Mexico. All we did was submit our passports and were then directed to the x-ray machine. Everyone had to get out of the motorhome (including our dogs) while the motorhome went through the x-ray machine. When that was complete the inspector at the x-ray machine gave me a slip to give to another inspector located at a final booth as we exited the customs/immigration compound. The whole process was less than an hour.