[Fulltiming]

I have the twin fuel tanks and unless I am going to be dry camping, I always leave the mix line open between the two tanks. That way, the tanks fall together. Each time I refuel at a truck stop with fill nozzles on both side, I close the valve, start the drivers side pump into the aux tank and start the passenger side pump into the primary tank. When the aux tank cuts off, I move that nozzle to the primary tank also so I am filling from both sides. As the primary tank gets close to being full, I cut off the passenger side nozzle and recap the main tank on that side so that I will not accidentally over flow the main tank. I will say that unless the fuel shutoff malfunctions or the coach is leaning to the passenger side, overflow should not occur anyway but my process minimizes the refuel time while maintaining the safety of the fuel shutoff.