It is extremely common with the 6.0l/6.4l heads. Id be willing to bet that every 6.0l/6.4l head has some cracks.

 

Yeah, that is very true. 6.4 heads all seem to crack the valve guides too.

I'd run the heads myself too. See if they can patch them up a bit and run them. Unless you can afford the new heads than just get some. I'd be willing to bet your new heads will look the same when you take them off again (if you ever had to)

 

Job2 6.0l heads and 6.4l heads are essentially the same thing. The only reason Ford changed them was with the anticipation of the 6.4l engine.

 

Goose350/Mdub perhaps you guys got something. So is this caused by chp being so high or heat (oops probably both as pressure causes heat)?... In terms of stress factor is what I'm looking at. My logic tells me if it is cracked now then it will only get worse. Truth is; yes I will continue to run my street tune on it if that makes a great deal of difference, however the gentleman I had mentioned earlier indicated his was bone stock and he still caught the virus. Dammed if you do or don't if that's the case. Looking at pricing 1600 or over if they don't like the condition of the heads you return. I'm sure they are re-manufactured too for that price. I'm gonna sleep on this one and probably go look at my heads in the morning. Just hate to put it back together and have it come apart with the current heads.

 

Heat has a lot to do with it, but in general it is the head design itself.

Id get the cracks fixed, hardened valve seats and run them. Or find some used heads in better shape, but id still do the valve seats.

 

I agree with this 100%. Every single thread I've read about a tuned 6.4 that took the heads off had every single valve seat cracked. EVERY ONE. The job1 6.4 heads are the same as 6.0 heads for the most part. I think the job2 6.4 heads had some changes though.

 

Morning boys. I'm gonna hit the shower then I'm headed to the Machine Shop to inspect the damage on the heads, Haven't made up my mind yet, hence the reason why I need to see the cracks and make an assessment from there. I'm still curious as to the surface plane of the head, (warped, out of tolerance, cracks). If the cracks are localized around the valve seats and surface can be salvaged without having to exceed max. tolerance and we are not looking at extreme expense, I'll give consideration. If we are looking at high dollar to repair then that is where the real decision will be made. I hate like hell to go out and buy re-manufactured heads as I don't know what they have been through. Man decisions, decisions?

 

They will be cracked around exhaust valves, I think they primarily crack between the exhaust valve and the water jackets. As long as the coolant can't leak in, or the boost doesn't leak out towards the coolant, it should be OK. It's not going to be cracked on the surface of the head where it mates to the block, it's extremely thick there. It cracks where the heat is and where it's the thinnest.

If the cost of repair is as much as reman heads then yes it would be silly to pay to fix heads.

 

Kiss of Death! Left head a couple of cracks around the valve seat I believe cylinder 4 & 6. The right head total different story. 3 cylinders had valve seat cracks and 2 cylinders had cracks from valve seat facing across to water journals, two places. I concluded that head was toast. Good mechanic and he said he could replace valve seats with hardened seats but said there was nothing he could do about the cracks going across facing. I asked him about replacement and he said new or re-manufactured heads is a toss because of the head design. In other words you might get lucky or not. They did not deal with acquiring heads, but suggested a Diesel performance shop down the road. I went there and he had a set re-manufactured ready to go to lay on the block. He cut me a deal $1407.25 (650 a piece + tax) out the door. Got them home and noticed they both are stamped "R" on the head which indicates they are right bank heads. After looking at the block vs. head, I can't see any difference in pattern vs. block interface. I think they will work regardless, but I do have call in to him to verify. In the mean time I"m busy cleaning the block surface for mating.
Thanks again guys for your help and advice. It is indeed appreciated by me and my two puppy dogs who hate it when I get pissed.

 

Thanks for the photos man! This looks like a bit more managable than pulling the cab... boy I wish I knew about this method before I did my head studs...