The 270 KM drive turned out to be 400 as I read the GPS wrong. The road was so rough and bumpy (they still charged $65 CAN in tolls) that it shook one of the dolly fenders to bits! We stopped at a roadside mechanico and four hours and $1200 pesos later ($400 materials and $800 labor) we were on the road again. The repairs look good but driving the next few hundred KM will tell the tale. I have photos but am too damn tired to take them out of the camera. I promise to post them.
We are in a Pemex about 40 KM from Villahermosa for the night. It was dark when we parked. It has been a long, frustrating day!