Well, were do i begin.............................

[dpantazis]

i am a geek......

guys-

i would be very leery of putting in mondo head studs. don;t forget that each component of the system has been carefully value-engineered by Navistar. sure, they may have skimped a bit on the head studs for the sake of manufacturing economy, but consider that they probably designed in a 'fuse' to minimize catastrophic failure too. similarly the installation of those fasteners would also be value engineered.

so being the geek that i am, i looked into the different head stud manuf's.

ARP: i am an engineer with a fundamental knowledge of metallurgy. i sat here reading it and wanting my desk references because it was so poorly worded and presented. i am actually a little offended by their catalog. they have crammed a whole bunch of engineering info into their catalog- its intimidating marketing. there is no need for all that gobledey gook in there. I actually wonder why anyone would manufacturer and market an alternator bolt that is 100x stronger than would seem necessary.

i find it curious that ARP only lists nuts not studs for the 6.0. maybe i am reading their catalog wrong.

reading the A1 Tech's catalog, its a more honest and better presented product. i don;t feel that they are trying to bully me into believing that their products are better and that i HAVE to buy their product.

anyhow, the fundamental difference between the H11 tools steel and the AISI 8247 is what those steels were designed for.

The H11 is a chromium hot work tool steel. the AISI is a high carbon steel. remember that these steel designations are 50-100 years old and their original intended uses are long gone. the tool steel in its nature is going to maintain its toughness at high temperatures and stresses, maintaining a sharp cutting edge. that is not to say it would work well as a stud.

the AISI steel is a general purpose high carbon steel with many different applications.
.................H11................AISI8740
Element......Weight %.........Weight %
C..............0.33-0.43.........0.38-0.43
Mn............0.20-0.50.........0.75-1.00
Si.............0.80-1.20.........0.15-0.30
Cr.............4.75-5.50.........0.40-0.60
Ni.............0.3..................0.40-0.70
Mo............1.10-1.60.........0.20-0.30
V..............0.30-0.60.........Not specified
Cu............0.25.................Not specified
P..............0.03.................0.035 (max)
S..............0.03.................0.04 (max)

Tensile Strength
(Mpa)........Not specified.......695.0, 25 annealed at 815°C more
Yield Strength
(Mpa)........Not specified.......415.8
Elongation
(%)..........Not specified.......22.2
Reduction
in Area (%).Not specified.......46.4

notice how the H11 does not quantify the Tensile, Yield or Elongation values? its because it is not needed for its intended application. this is not to say that EITHER is better. its only to show you how each alloying element is controlled and what properties are being tailored.

when you get to these levels of performance, either is going to be way stronger than stock.

but like i said before, be making the head studs stronger and almost stretch - proof, now you are going to be stressing the next weakest link in the system. thing is, what is that going to be? the gasket? the head? the threads in the block?

dennis

 

[BamaSixGun]

SO, in your geekish opinion, which would be the better head stud for this application, based on your knowledge of their make-up and or design?

 

[dpantazis]

bama- i would not even entertain it at this point, even if i had the money.

you said SCt? i thought you were running the banks stuff. ???

see what the tech says. iirc, you have had 3 egrs done? a turbo? did you get the degass bottle recall where it lowers the coolant level mark? checked the radiator cap?

if it WERE a head gasket, do you trust your dealer? ask them what the warantee is going to be on the repair (? 12/12) and what their thoughts on upgrading the head studs are. if you upgrade and the gasket blows again, will they warrant it with upgraded studs?

dp

 

[bushpilot]

i saw 08 tail lights on a 99-07 looked like **** to me...they dont
mount flush...they stick out past the body work !

 

[Maxtor]

Bama;

All this might just be for not. Have your radiator checked for exhaust gas. A good shop can tell you where the leak is and if it is or is not the head gasket.
If it is a head gasket, and it was my truck (I take that back, because mine is under warrentee), I would go with the aftermarket head gaskets, and if there is room, use the head studs. They will give you more even bolt torque, and stronger bolts.
In a race car, we would always use head studs, when we had the room in the engine compartment. It is not as easy to remove heads when they have studs... It takes more room to remove the heads. Another advantage, was that it was easier on the blocks threads, if you have to remove the heads often.
It would probably be a good idea for all of us to tighten the head bolts at regular intervals on our psd's, especially when using a power adder.

 

[BamaSixGun]

bama- i would not even entertain it at this point, even if i had the money.

you said SCt? i thought you were running the banks stuff. ???

see what the tech says. iirc, you have had 3 egrs done? a turbo? did you get the degass bottle recall where it lowers the coolant level mark? checked the radiator cap?

if it WERE a head gasket, do you trust your dealer? ask them what the warantee is going to be on the repair (? 12/12) and what their thoughts on upgrading the head studs are. if you upgrade and the gasket blows again, will they warrant it with upgraded studs?

dp

those are all good questions DP. and yes, 3 egr coolers, 1 turbo, and yes on the bottle recall.

and yes i do trust my dealer. i will be sure to ask them all the appropriate questions.

i still have the banks, but have not ran it in over 3 months.

 

[BamaSixGun]

i saw 08 tail lights on a 99-07 looked like **** to me...they dont
mount flush...they stick out past the body work !

bush, i am talking about the tailgate, not taillights.

they stick out on the 08's too. its a new design.

 

[Crumm]

Crummy:
dude, dont knock me down even more than i am right now. i can still represent SDD as the April DOTM. this is just one of those set backs that happens sometimes. this was the first time i hooked up in over a month. i was only helpin my cousin out, still no plans of goin back on the road. i still want to sell the trailer.

I was trying to put a grin on your face when you were having a bad day. Did not mean to knock you down but I guess my attempt was a failure so I am Sometimes my sense of humor does not come across the right way Good luck on the repairs.

Crumm

 

[BamaSixGun]

I was trying to put a grin on your face when you were having a bad day. Did not mean to knock you down but I guess my attempt was a failure so I am Sometimes my sense of humor does not come across the right way Good luck on the repairs.

Crumm

i know you were tryin to cheer me up crumm, i was just makin ya feel bad, sorry.

i sure it will all go well.

 

[bushpilot]

bush, i am talking about the tailgate, not taillights.

they stick out on the 08's too. its a new design.

yeah my bad on the tail lights...i didnt like 'em on the 99-07 that
i saw 'em on.

tailgate is apparently an issue TOO on the 99-07s...it doesnt close
or fit flush.