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Just recently got done doing all the deletes on my 2011 Larime. I was wondering what makes the OEM head studs so bad they need to be replaced with aftermarket studs. What makes aftermarket so much better? I will proabably change mine out after awhile just based on what I have read on here and for the peace of mind. Looks like installing studs would be alot cheaper then a whole head gasket job.
 

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Big thing is allowing to truck to fully warm up prior to putting your right foot to it. There are quite a few people running around on stock studs without any issues. I have about 12,000 deleted miles with zero issues but I don't beat or rod on my truck prior to it reaching operating temperature. And when I tow I tow heavy. Around 28k gross probably.


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Stock head bolts aren't near as bad as people think. Most of peoples failures could have been prevented.

Like others have said warming your truck up properly is a huge one. The other big cause is too much timing with aftermarket tuners. So many people have blown there head gasket because they simply didn't understand what tuning they were using.

High drive pressure honestly is probably the least likely to blow your head gasket. Another thing that gets blown way out of proportion. I'm not saying it can't happen but usually it happens if the turbo is broken and stuck in the closed position and the back pressure gets extremely high.

There are lots of guys who have put down 500+ on dynos with stock head bolts.
 

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Not sure if it applies, but I read an article a while about about Harley Davidson motorcycles and their expansion under operating temperature and at ambient temperature. I can't remember the specifics, but it underlined the necessity of letting the engine come to operating temperature. The expansion of the block vs. the head bolts increased the tension applied by the head bolts to the heads by a pretty significant margin.


I guess, long story short: The engine is made to run at operating temperature. Take it EASY until it's there. Having read these forums for a while now, I think the 6.7 the same way. It will tolerate a lot more HP but it needs to be at 200*F to do it.
 

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Big thing is allowing to truck to fully warm up prior to putting your right foot to it. There are quite a few people running around on stock studs without any issues. I have about 12,000 deleted miles with zero issues but I don't beat or rod on my truck prior to it reaching operating temperature. And when I tow I tow heavy. Around 28k gross probably.


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^^ what he said

I don't always have time in the mornings to let my truck idle long enough to warm up, but I know if the truck is still cold, use light throttle, your hg will thank you.
 

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Drive pressure causes the head to lift, which blows the gasket.

Aftermarket studs are less likely to stretch and allow the head to lift.
OK, explain to me how less then 100 PSIG drive pressure will lift a head when compression pressures are around 500PSIG and combustion pressures are over 2000PSIG don't.
 

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the compression and combustion pressures are used up in the natural cycle of the engine running (compression ignites the fuel, combustion turns the motor). Drive pressure on the other hand doesn't. It gets trapped, so something has to give.
 

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That is one of the DUMBEST things I have ever heard! You really don't know what you are talking about. If it that bad why are you not blowing the turbo and exhaust manifold gaskets?
 

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That is one of the DUMBEST things I have ever heard! You really don't know what you are talking about. If it that bad why are you not blowing the turbo and exhaust manifold gaskets?

call it what you want, but everything stated here is factual
 

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Well then I'm confused. If that's the case and I'm full of baloney (which I def. could be) then why do people waste their hard earned money on wastegates?
 

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Well then I'm confused. If that's the case and I'm full of baloney (which I def. could be) then why do people waste their hard earned money on wastegates?
VG turbos dont have a wastegate.......
 

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my point. When people upgrade fueling and exhaust manifold I see guys getting wastegates...if drive pressure isn't an issue then why would they do that?
 

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if you tried to run a wastegate on a VG turbo, it probably wouldn't spool very well and I'm sure the EB wouldn't work
 

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i dunno. It just seems to me like the majority of HG issues comes from aggressive tuning, a heavy right foot, and the factory turbo (which is restrictive by design). From everything I've encountered/read everyone has their own theory on what causes a HG to blow, but I have not seen any one instance where there has been a definitive answer as to how/why it happens. I think it's the version of trying to put 10lbs of **** in a 5lb bag. Unless you upgrade everything together (like a matched set) you'll have a bottleneck. And pushing an engine without mods past it's engineered power level is asking for things to break.
 

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like said before the egr cooler acts as a wastegate, per say, by consuming some of the drive pressure. when you remove the cooler pressure increases all across the board.
 

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OK, explain to me how less then 100 PSIG drive pressure will lift a head when compression pressures are around 500PSIG and combustion pressures are over 2000PSIG don't.
It's not the drive pressure by itself that will cause the head to lift. That's where what he said is wrong. It's high drive pressure combined with high cylinder pressure. If you have high drive pressure it's allowing less of the exhaust to exit the cylinder... meanwhile the turbo is forcing more air in from the other side creating higher cylinder pressure on the compression stroke or at combustion. The problem just compounds. So like I said, it's not the drive pressure alone that's the problem. It's the drive pressure not allowing the exhaust to leave the cylinder properly that's the problem he's referring too.

However I don't believe that only drive pressure is to blame for HG failures. Tuning and timing (compared to the amount of fuel being injected) are the biggest part of it IMO. But I think the drive pressure/cylinder pressure does play into it a little....
 

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Some feel leaving the EGR on after deleting helps with drive pressure. It does not. It is computer controlled. Once deleted it will not open no matter how much pressure. The head gasket thing seems to have some things in common for the most part. To much timing, setting defuels on 2010 and later trucks and getting on it when cold. For the most part.
 

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like said before the egr cooler acts as a wastegate, per say, by consuming some of the drive pressure. when you remove the cooler pressure increases all across the board.
Ime not a believer in the EGR cooler acting as you said. I got 120k on my truck with no blown head gaskets.


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Ask yourself this, does using an exhaust brake blow lead gaskets? Again the turbo to manifold and the ex manifold to head are MUCH less stout as the head to block. IF backpressure would blow a gasket it would be on of those.
Lets look at what is happening inside the motor, air enters the cylinder during the intake stroke. The intake valve is open and the piston is moving down. after bdc the intake closes and the air is compressed to around 500 psig- enough to heat the air so that the fuel in nights when injected. On earlier mechanical injected engines that was a violent explosion that caused the "Diesel rattle" this is way more pressure and heat, and vibration then the little bit of backpressure. After the piston moves down from the pressure of the expanding gas the exhaust valve opens. The pressure is still way more than any backpressure, if it wasn't the engine would not run. I have worked on a few cars that the exhaust was plugged enough that it would not run and it never blew a head gasket. Now the piston in moving back up pushing out the Burt gases and driving the turbo. As the piston reaches tdc the exhaust closes and, at the same time the intake opens, valve overlap. Then the piston starts back down. Any residual exhaust pressure that was there is gone, the ex valve is closed and the piston is moving back down taking in fresh air for the next cycle.
 
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