As if 30 gallons of fuel isn't enough. As far as I know, only the Suburban has a larger standard fuel tank, 42 gallons if memory serves.
My F-350. short wheelbase, came with a 29 gallon tank. A company in California made a 46 gallon replacement tank which I had installed at their factory. Great decision.
Because I could come to the factory, they had a special deal with a reduced rate at at a local motel, so I came the night before, showed up early in the morning, they removed my fuel from the OEM tank, installed the new 46 gallon tank, then pumped in my fuel. $100.00 plus the cost of the tank. This in the year 2005.
These days I always put in fuel preservative in the diesel fuel I use.