head's are always a problem on these trucks. I blew two sets of headgaskets on mine before 60k. Once with stock TTY bolts and once with ARP studs, but they were dealer installed studs, and the heads were not decked. I think the whole job was mucked up. I have been running tunes again with stock TTY bolts back in it with the same heads and it's holding fine now... so what does that tell you? Some stock trucks have issues with it.

 

i have pushed 27-28 psi on stock bolts and have yet to have any issues, and i have been beatin the **** out of this truck

 

I've hit 35+psi with my current setup on the stock TTY bolts again... still holding, but it's already blown twice.

It's not so much the boost, the timing is really what does it. Timing drastically increases cylinder pressures.

 

if ford knows they have a problem with the head bolts then why dont they recall them

 

They've turned the blind eye to it. It's far easier to blame the guy with the truck by saying he was using a programmer or something. International originally designed this motor to have less than 200 hp from what I remember. Ford bumped it up to 325, and added emissions controls to it. The head design just sucks. There is only 4 bolts per cylinder, instead of 6 like the 7.3. They did make the bolts larger on the 6.4 (still a 4-bolt per cylinder design) and they seem to hold a little better, but still a problem.

The real issue lies with their specs for flatness on the heads and how they check it, and the fact that they will not deck or machine their heads at all. I've heard NEW heads from Ford come in out of spec sometimes.

There has been many lawsuits, buy-backs and lemon law cases with this motor and Ford. It pretty much put the last nail in the coffin between them and International, thus their new built in-house engine this year.

 

Some trucks are fine with stock hardware. I towed and dd on my SRL tune. My truck was tuned for 2 years straight, never went back to stock. Sled pulled and went down the strip. All on stock hardware.(Still stock too)

 

Exactly, you get guys like this who run tunes hard daily with no issues, and then some trucks just fall apart looking at them.

There is a guy in our local diesel club who has an 03 6.0 and runs Erics x-race daily, hasn't had a single issue with his truck.

 

I know the 6.7L is Fords Design But I Heard Navistar is still building it

 

I wouldn't say hasn't had a single issue Mike, I need tires again!!!

 

You heard wrong. Ford is building it. Peugot helped design it. It's still technically a Ford designed and built motor though. Navistar and Ford are no longer working together on the small stuff. I think they still supply Ford with motors for larger trucks.