We have driven to Jalisco several times with our truck and 5th wheel. We have always been told by others to use the Periferico (truck route) to go around Navojoa. This is a longer route with horrible roads. Do others take this route or simply drive through the town?
It takes a little longer to take the truck route, but it's easy as long as you watch for the topes and the speed limit. This is the "official" truck route that starts north of town at the big Pemex with the light.
Through town? The alternate old bus route starts just after the bridge going south, and is quite bumpy. Remember, the bus/truck route through town is on the INLAND side, it's bumpy, but has few lights.
The one time we were pulled over, we were in an older RV that didn't have shoulder straps. The cop asked, saw the lap belts and sent us on our way. After that, we used the official bypass.