air front does exist but is incredibly uncommon, will never ever be found on a fleet truck like that.
motor probably due for inframe at that price. I think ISM are usually due at around a million miles, same as most of the big'uns. trans could be any of 3 different things with that description, one of them good, one of them a matter of preference that my dad hated and I think I'd dislike, and the other an unlikely automatic.