We won't ever know if the bolt tightening procedures were properly followed on all the engines produced. I tend to think not ...............

Seen a lot of manufacturing over the years and not one of them has been perfect as to following procedures - even heavily regulated industries. Even automated assembly can periodically have significant issues! There is a lot of variability in who has success with head gaskets and who doesn't.

All we can do is to manage what we are able to (ie temperatures, the tunes we run, how we drive, and to maintain critical sensors like EOT, EBP, MAP, MAF, etc).

 

That's not another variable I going to do with a maybe this and maybe that.

We know the service pattern was changed, but those bolts are individually tightened. But as far back as the 90's, I know in the gas engine side of the few plants I saw, the heads were gang run by CNC. Back in ~2005 when I was at the Freightliner plant in South Carolina, things were very automated and controlled. But like all assembly plants, sub assemblies like engines and transmissions came full assembled.

The history of failed head gaskets to me evolves around pushing the engine with tunes, at some degree. Are there variables in assembly and production, sure. Typically they come in under 1 percent. I know for a fact because we lived it more than once, when warranty gets to 1% Starts getting hyper, and at 3% Ford goes nuclear. You will have Ford engineers at your plant checking things and telling you what to do to the point you don't want.

I agree with you what we can do is good maintenance, good monitoring, and be reasonable.

 

Lots of people had issues with stock engines. It became a big warranty issue and a fight between the two companies as we all know, so it was probably greater than 1% I gather. Ford's position, at least for a while, was oil coolers plugged caused EGR cooler failure due to excessive cooling temps, which leaked and caused head gasket failure. Stock engine issue. That said, there was a lot of variability around that. In other words, not every plugged oil cooler caused EGR failure. Not every EGR failure took out the head gaskets. Ford also stated that over boosting could take out head gaskets. At what point we don't know really know. Depends on fueling, temperatures, injector performance, etc. I think we all remember a few claims of some low level tunes that were head gasket safe even. Who knows if they were. Lots of variability in experiences.

My point is that sifting through all of this is really impossible (I believe that is consistent with your perspective as well). Additionally, Ford would certainly deny warranty repair if ANY aftermarket equipment was installed. Some head gasket failures were denied simply from an installed bypass coolant filter. The failure data is not very useful in the 6.0L case IMO. Too many possible contributing factors (temperature, boost, fueling, and as you put it "casting variability"). It didn't take long for Ford to start getting nervous about the warranty costs and the publicity. That skewed the data as well. This behavior might have even lead them to issue new heads and call them commonized for upcoming 6.4L production. We deal with what we can see and quantify, and that certainly seems to be plenty to try to manage in the 6.0L!

Maybe the head casting "cupping" issues you brought up contributed to issues in the torquing or the "even" torquing of all the bolts. I would call those 'cupped heads" as manufacturing failures. 1% or more - who knows.

Anyway, my supposition of issues in manufacturing consistency was just a comment. Not all comments are intended to get action or response - just thinking out loud. Clearly it isn't anything a person can validate and clearly not even worth trying. I have seen failures in following prescribed equipment calibration procedures cause the recall of hundreds of tons of bulk pharmaceuticals due to color, and or metal, contamination from bulk blenders that didn't maintain proper orientation of the blending mechanism (poor torquing). It happens sometimes. Who knows, maybe International was more careful, and if not, it probably wasn't a huge percentage out of all the 6.0's produced - to your point (but still could be thousands of impacted engines even at .5%).

 

Oh, I agree there were many issues with the stock engines. Injectors, turbos, coolers, the list goes on. However, I hedge a little on the head gaskets because I know of quite a few people who did not tell they used a tune, had a mechanic friend, and even service managers who let it go when there was a tune.

There also is the issue there were multiple variations of the heads, I think in total 5. No one talks about that.

I'm pretty sure all the heads will develop that cup. However, there is a flaw in how those castings were designed; there is poor support where the intake runners meet the main area in the head. They scalloped the supports outward from the bolt pedestals, and the head "frame' is boxed at the intake. They should have boxed fully inward at the bolting locations. I measured how much force it takes to straighten the heads and made a contact pattern of the heads. Not with PreScale, but carbon paper. I think the PreScale would come out to $500 to do that. Fel-Pro does it; we used to do it at the hub/rotor/wheel juncture years ago. I probably threw out what I needed when the facility closed. Despite the cup, the pattern looked good (no gasket).

 

No doubt there were many Techs that covered for friends (especially early on), but I don't know how long that lasted. By the time I bought my first one in '05, the phrase "you play, you pay" had gotten pretty common. Most techs I knew were very open about their position (ie even their grandmother got denied warranty coverage if she had a tune). Seemed to have a lot to do with how poorly Techs get compensated on warranty repairs - or at least that was my take.

 

I would agree by '05 things had tightened up.

 

Pretty sure the root cause was the tuning on the 6.0PSD had cylinder pressures above specification. I do remember getting a recall on my truck which required a reflash, reduced antifreeze in the degass bottle with a new label indicating the new fill level, and many suspected with myself included was Fords attempt to maintain advertised power levels., but reduce overall power to mitigate this problem. Also I recall magazine articles also confirmed the reduced power levels of the 6.0PSD on dyno tests.

Here's a copy/paste on a document anyone can search and review:
In another damning revelation that emerged at trial, Mike Frommann, a Ford warranty manager, sent an email to his colleagues warning that the problematic 6.0-liter diesel engine could lead to a class action if its cylinder pressure specifications were made public, and instructed them to delete emails referencing the 6.0-liter's problem

 

With my '04 IIRC I had blown head gaskets within a year or so, and fixed under warranty. Of course it was probably my doing for not understanding the deficiencies of the engine and running an old superchips canned tunes programmer. As a first diesel owner I thought the engines were solid.

They fixed it under warranty. The second and last time it happened again because of canned tunes and not monitoring correctly as I do now.

As Jack mentioned, it seems these trucks in stock form do not like increased cylinder pressures and canned tunes. Also who is to say it was even repaired correctly since it was closely after its release.

The more I became familiar with the truck the more I was disappointed in what I had gotten myself into. I settled on the FORD because of the cab size compared to the chevy (which I would never buy an IFS truck again) and the Dodge who had a crew cab but it looked like an extra cab.

Nowadays, after going through the growing pains of being a new 6.0 owner, I am very happy with the truck. 18 yrs and she is solid now.

 

Troy, I've read the details about the trial. The problem with Frommann is that he was brought in to deal with the volume of issues, but there is no record of his background. I tried to look him up every way I could, and his history was nowhere to be found. If he came out of the gas engine side, a diesel compression ratio and its combustion pressures are so far out of the norm for a gas motor; he would be floored. However, if he was referencing the combustion pressure vs. the bolt spacing, Frommann had a point in my view. But, again, increasing clamping force is not going to fix that.

So instead of "the 6.0PSD had cylinder pressures above specification", I would say the bolting pattern was out of engineering standards.

My understanding about the reduced power was during warmup, and yes, it was noticeable on the trucks we would get from Ford as test beds. I let my employees take my truck out if they wanted to; it still had the original '03 pilot injection and good power off the line.

Joe, I take issue with Ford's procedure and limits with the service repairs. A bow of up to 0.002" is unacceptable for a head where the bolts are so far apart. That is your new starting point for elastic deformation so that you can end up at 0.004" under high loads. No head gasket is going to tolerate that. Not to machine the heads to get any bow out is the wrong procedure, again, with that head bolt spacing. Also, all the engineering textbooks on engines and head gaskets bring up the point of the head and block surface finish and cleanliness. Ford ignored that aspect, which I believe also impacted the repair success. Razor blade clean does not do that. I reference several situations in that video where an owner had the heads milled, and the gaskets did not blow. Whether they had the studs or not did not matter; the guys who used them and did not mill the heads had a repeat failure.

O-rings keep the gaskets from moving; a head with a thicker bed plate like the 20mm seems to do better, and if they had incorporated the reinforcement they used in the 6.4L head into a 6.0L head, that should have been best.

I don't have an issue with people using studs. I have a problem with people thinking the studs, torqued to approximately the same compressive load as the factory bolts, will solve the issue when I believe it's about the design - bolt spacing and head flexibility. And heads that tent in the center for whatever reason.

Engineering textbook on automotive gaskets. The out-of-flat specs are respective of proper bolt spacing, which should be no farther than 4 bolt diameters. The 7.3L had that; the Cummins had that. The tighter spacing would pull the bow down and prevent the dynamic distortion.

 

Assuming studs do not help anything regarding head gasket leaks. Then one could assume that my last 11 years of successfully running with an SRL+ tune could have also been done with the head bolts. The SRL+ is not a mild tune either.

Hmmmm

No doubt commonized 06's and 07's had head gasket failures, but it would be interesting to know percentages (which of course we never will).

 

And percentages of stock vs tuned. Even stock 18mm heads have reports of a good life. But I didn't have good luck finding pure stock 20mm engines with failures. Maybe you hunt better.

I see it as depending on what the tune's combustion pressure is, and how much you are into the throttle.

The preload of the factory bolts is probably as ARP says, slightly below the values of the ARP standard studs. Going back to Frommann, if his comment is about Preload vs. Pressure, each of the four stock bolts may have a Preload of 23,000-24,000lbs at the yield, which is below a 25,000psi combustion pressure. That would put the stock safety factor of four bolts at 3.68:1 rather than 4:1. If Ford's safety factor standard is 4:1 it fails that criteria, Frommann's hair is on fire, but it's still 3.68X the stock combustion force. It's hard to lift 368lbs over your head when you can only push 100lbs. It tends not to move.

Again, the fasteners cone of pressure is far from where we see the gaskets fail.

 

So you don't think there are many (fairly) heavily tuned commonized 06 or 07 6.0's that ever blew head gaskets? Or, if there are some, then poorly written tunes or maybe other factors like blown EGR coolers or overboost was the primary cause?

 

You guys are making me want to put a tuner on my truck just to test the commonized head strength.

As far as I know the motor is completely stock, 130k miles. Zero signs of headgasket issues. Highest EGTs I've ever seen are 1300 when towing up a long hill. It did have a replaced EGR cooler when I bought it so when that failed it may have hurt something but so far no signs. Still need to get my coolant pressure gauge installed...

 

That is what it sounds like the logic tree is saying! Just watch temperatures and boost (oh and maybe choose the tune wisely)!

That said, there are plenty of potential pitfalls!!

 

Just catching up some - I met a fellow FTE'er and PM'd/emailed as it turned out we both lived in the same town, He bought a '06 new and slapped a 100HP tune on it (don't know which one) and blew the head gaskets, the dealership did a head gasket job under warranty, he sold it as soon as he got it back - I think he only had it less than a year, maybe as little as 6 months. So answering one question, at least in this case, the failures were still being covered on '06 my. Now what I don't know is how early an '06 he had. Maybe I'll see if I can find any of our comms and maybe fill in some blanks...

Edit: tossed old PMs I guess - I got to thinking that we had our '07 when I was talking with this guy - so timeframe is after 8/06 - still no details and who knows, maybe the dealer did it on goodwill...