I have a 2004 F-250 with the 6.0 liter diesel engine that is notorious for many mechanical issues.  I now have 24,000 miles on the truck and have had (under warranty) the turbo, turbo base plate, two batteries, two recalls (wiring harness & re-flash of the computer), oil leaks, and two TSB’s (technical service bulletins), etc. 

All of the miles on the truck have been hard miles, I only run it when I’m pulling my 26 foot car hauler (12,000 lbs) or the TT.  The truck has never left me sitting on the side of the road but the trips to the dealer have been a really big inconvenience, especially when you consider the low mileage.  I don’t run any aftermarket chips to improve the power and I have not altered the exhaust system, the truck is totally stock.  I am extremely particular about maintenance, the oil and filter have been changed every 5,000 miles and the fuel filters (both) @ 20,000 miles.  I buy Motorcraft filters and run Rotella 15W-40 oil. 

 I am constantly looking for ways to increase the longevity of the drive train, especially now that the truck is out of warranty and I will be paying for all of the repairs.  If you Google the 6.0 engine you will find a wealth of info (some good but more of it bad) on the internet.  Main problems with the engine seem to be head gasket, oil cooler, egr cooler, egr, turbo, injectors, etc.  The most popular modification seems to be the addition of a coolant filter, this is supposed to reduce the possibility of a blockage in the oil & egr cooler, which will cause the engine to overheat and ultimately lead to head gasket failure.  The blockage is caused by sand left in the cooling passages of the block and heads during the casting process.  Your commercial trucks and DP motor homes have been running coolant filters for years and they claim that it will extend the life of the water pump, heater cores, radiators, etc.  I guess having sand or other contaminants in the coolant would cause damage to the rubber seals on the water pump and block small openings in the cooling system.  I can't figure out why the manufacturers didn't install a filter as standard equipment.  The dealers and mechanics (diesel mech) I have talked with, all recommend the coolant filter.

I know that most of the people that pull full time and for recreation use the Ford truck as their tow vehicle and that is the reason I put this out there…just food for thought.  I have installed the coolant filter on my truck in hopes of increasing dependability & longevity.  I would never consider owning anything other than a Ford Super Duty because they are the best tow vehicle on the road. IMHO 

I did the coolant filter install for around $60.00 and I recommend that you purchase the kit from Napa/Wix so the filters can be purchased @ most local parts houses.  The 6.0 does not require the filter with additives (chemicals) but you should only use the Motorcraft Gold (diesel) coolant when you do the install or just top off the system.  You should also use distilled water to mix it 50/50, never use tap water.

I will include a couple of links to the discussion forums and places to purchase the kits. Let me know if you would like to see pics of my filter install and I'll post them.  This setup can be installed on all diesel engines; it's not just the 6.0 liter that can benefit from it.