I agree with you in the 6.7 and the 6.0. The 6.4 isnt a total loss. i have a 6.4 f550 bucket truck at work and it runs awesome, but you are dead on with the fuel mileage. The 6.7 is such a smooth running truck we also have one of those in our fleet. But I do have to say that I love my 6.0. Its an awesome truck, i did have to fork out quite a bit of change, but it was well worth it.
We had a 6.4 bucket at work, was a pig on fuel.Never drove a 6.7 but the price is out of control for a Lariat.My 6.0 suits the bill and it's payed foy and it's only got 68,000 on it so it's going to be around awhile......my 2 cents
I've heard quite a wide spread in MPG numbers for the 6.7. Our F550 hauler at work gets about 9 MPG loaded but being licensed for 39K lbs. I wouldn't expect it to be great. The driver says it will "make speed" going up hill with that load If he needs it to. The power with that thing is flat crazy. I have talked to several folks that get 17-21 with stock crewcab F250/350 4x4's IF they maintain 65-70 mph.
The 6.4 I have no knowledge of except that they can make some crazy HP #'s but are high maintenance.
The 6.0 is much easier to work on than the other two, but it has well documented weaknesses also.
I drove a 6.7 F-350, it drove like a gasser, accelerated like a gasser and sounded like a gasser, except that it had a lot of power. I hear they have issues with DEF, and fuel pumps, but that's all I know...
I feel sorry for the 6.4 guys and we came very close to buying one (boy was that luck). The guys that seem most happy with them undo the emissions crap and tune them. They become more reliable and can get decent mileage. But.... Like Josh, I spoke to several diesel techs that say there really are just too many issues that don't have solutions. Whereas the 6.0 seems to be much more of a known for it's problem areas and the same techs said you do some bullet-proofing and stay on top of things and it's a good platform.
Only thing I know about the 6.7 is from what I'd read up on a while back when a friend was buying one. The early ones had potential issues but it seems like later in the run they've gotten better.
As for me, even the 6.0 has too many complex systems it relies on, it's probably like times 4 stepping in to a 6.7. As once was said: the more things that can go wrong the more chance that something will go wrong...
Having no experience on the 6.4 or 6.7 I went to both of those forums to see if I could get a feel for what FTE members had going on. The 6.4 forum had a fair amount of technical stuff going on and even some talk of coolers, tunes, cats, radiators and overheating, and several post on getting the d@##ed DPF deleted.
On the 6.7 forum- 1 post about a fuel problem the dealerships can't figure out while the OP is on vacation, (described as a "nightmare") and is complete with musings about buying a Dodge. Another post where a broken glow plug lunched the engine. The rest of the tech stuff is fuel injector clamp and dead battery. A few posts on airbags and sway bars and towing, one or two "I love my truck" threads and the rest is satellite radio, blue tooth, seat belts and warranty.
Think I'll stay here in the 6.0 forum .
Some stats from right now: 6.7 forum 115 viewing. 6.4 forum 68 viewing. 6.0 forum 311 viewing... Not sure if that's good or bad?
To those of you who say the 6.4 has many issues, what are these issues you speak of?
I don't have much time here so I'll be quick:
Generally they're referred to as "oil makers" because the DPF regen is via a fuel dose on the exhaust stroke(s) and folks figure that IS the fuel they are measuring too much of in their used oil analysis reports.
Fuel system is HP and virtually anything not fuel will cause the HPFP to pretty much come apart and send all the little metal chunks throughout the fuel system.
Coolers, all of 'em. Radiator, EGR, etc. they are having repeat problems with them.
I gotta' go -- just thought I'd get something more out there to answer your Q