Letting a Class A sit for a month or two but full timing

Due to Med problems DW and I have not used our 06 Revolution in four years.I take it out often and run it around for 50 or so miles and then back home for a few more months. This sucker has Six NEW,NOW THREE YEARS old, tires which have less than a thousand MI on them. It is still running like new. I Do start the engine often, (Just to hear that diesel roar)