what is a reasonable mileage to expect for a 7.3? I just paid for and am awaiting delivery of the title and paperwork of a 1999 F350 4wd dually. I drove it about 10 miles when inspecting it, and then another 80 miles back to the storage lot where it is currently awaiting the paperwork. I cannot operate it until the new title arrives. base is pretty strict on some things.