I just bought a 2004 f350 (6.0) Lariet with 16,000 miles. Can you guys think of anything that I shall have them look at or change(filters,lubricants.etc.) I just had motor oil changed and I know that fuel filter is due. This truck is used daily for my landscaping business towing a trailer and a load everday, so upkeep with maintenance is a must. Shall I change coolant to be safe?