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Old Football Coach said:
What is easiest and best strategies for gassing up diesel while in midtrip. I have F350 pulling 36ft 5th wheel
Truck lanes at truck stops have high speed pumps, and the filler nozzle is a wider diameter than the F350 fill port. My 1999 F350 uses the same diameter nozzle as you'll find on gas hoses, so even if the tank could accept the faster fill rate there's no way to fit the larger nozzle into the filler neck.
This means you're restricted to using the automobile pumps or the RV lanes in places like Flying Js. Usually stations that have diesel on the automobile pumps have it on the outermost sets of pumps, so this makes maneuvering a truck and trailer in and out a little bit easier.
It's wise to be aware of the overhead clearance, but most gas canopies have over 13'6" clearance, which is the highway height limit. If they're lower they'll almost always have the impaired clearance marked on them.
Diesel motorhomes have larger tanks and fill necks that can accept the larger nozzle, so they can use the truck pumps if they want.
I have only had to stop once so far, and it was at truck stop, they were 3 and 4 deep at each pump filling up trucks. Many of them were just sitting empty waiting I guess. Is this norm?
The protocol in the truck lanes is to pull forward when you're done fueling, then go inside and do the paperwork. This lets the next truck in line pull up to the pump and start filling instead of waiting for the first driver to come back out.
It can take 10 minutes or more to fill a truck's tanks even with a high speed pump, so yes it can seem like the line is moving slowly.