Head gasket time already?

[roaniecowpony]

BS meter is pegged. The reason people beef up drivetrains for off road vehicles is because of HOW the torque demands are being placed when rock crawling. Also for physical protection from obstacles but that’s another topic. It really doesn’t have anything to do with increased drivetrain mass via larger tires. The torque rating of an engine is the torque rating of an engine. Rock crawling places VERY unique demands on driveshafts and axles.

Also, to make an extremely important point, engines don’t have a clue what size your tires are or what your gearing is. ECU’s can be programmed for these changes for various reasons (speedometer, etc) but it doesn’t demonstrably change how the engine itself makes power. The engine “knows” fuel/air mixture and the associated rpm. That’s really it. You ask it to go via your foot, it obliges. Increased drivetrain mass takes more engine power to move due to inertia just as towing does.

To assert that large tires is somehow orders of magnitude harder on an engine than max towing is wildly inaccurate. Under certain circumstances, one or the other could be equally as harmful in the long term. Weight is weight. And yes, all weight on a vehicle isn’t created equal. But they aren’t orders of magnitude different.

All that to say, head gaskets aren’t blowing due to 37s. /rant

A gear reduction system is a torque mulitplying system.

Sponsored

 

[Franger]

A gear reduction system is a torque mulitplying system.

100%. No debate there. And I want to point out that I’m not taking an extreme viewpoint here. I’m merely saying that in the context of this conversation and with an eye towards head gasket issues in the Pentastar, gearing and tires aren’t enough on their own to result in a preponderance of issues. If gearing and tire weight are such an issue for drivetrain stress, I’d imagine we’d see a load of issues with the 850RE too. It’s only a 500NM transmission (~370ft/lbs).

BL: any V6 *should* be able to operate at slightly elevated RPMs and not blow up. As Alphawolff pointed out, this is a bolt torque issue and happens most frequently at a certain mileage of the engine. Thoughts?

 

[roaniecowpony]

100%. No debate there. And I want to point out that I’m not taking an extreme viewpoint here. I’m merely saying that in the context of this conversation and with an eye towards head gasket issues in the Pentastar, gearing and tires aren’t enough on their own to result in a preponderance of issues. If gearing and tire weight are such an issue for drivetrain stress, I’d imagine we’d see a load of issues with the 850RE too. It’s only a 500NM transmission (~370ft/lbs).

BL: any V6 *should* be able to operate at slightly elevated RPMs and not blow up. As Alphawolff pointed out, this is a bolt torque issue and happens most frequently at a certain mileage of the engine. Thoughts?

I don't like the "open deck" unsupported cylinder deck design of the pentastar. I don't like the new PUG intake VVL cam/rocker design. They went from one problematic design to another. I don't think 4 chains in an engine is reasonable.

 

[XtremeRetard]

Engine RPM is not going to be in the right range unless its geared accordingly. Sure you can drive around at 5000 rpm in 3rd gear at 70mph if you want with stock gears and 38" tires, but...

 

[bikenutty]

got a call yesterday, "some" goodwill was offered, I am still required to pay almost $600 out of pocket. Better than a stick in the eye. Told them go ahead and replace the head gaskets.

I don't fully understand why I have to cough up anything for a defect that is known. Hopefully this repair will not be a Band-Aid. A little nervous take any long trips after this.. I guess time will tell.

fingers crossed

 

[roaniecowpony]

Put higher octane gas in it, get the RPM Extreme fan controller, put the best 30 or 40 grade oil money can buy in it , say half a dozen hail Mary's and drive it like you own it.

 

[Franger]

Engine RPM is not going to be in the right range unless its geared accordingly. Sure you can drive around at 5000 rpm in 3rd gear at 70mph if you want with stock gears and 38" tires, but...

Okay I agree and that’s great but…

Is that what we’re talking about here? Again, in the context of THIS ISSUE (head gaskets, shoot, add in the lifter issue too!), is a 3.6L pentastar more prone to have the issue if the gearing is off? Just how big would tires need to be and how sub-optimal the gearing for the engine to avg 1000rpm or more than an optimally geared vehicle in a given speed/load/grade/altitude range? What’s the engine designed for? Should every jeep come standard with 4.56 or 4.88?

 

[captainstabbins]

I just had the head gasket on my 2.0 replaced. I was 1 month out of warranty. 59,000 miles. I had an extended warranty so it was covered but not just the 3.6s having the issue.

 

[Jamrock]

From what I have seen, head gaskets don't usually go bad by themselves. I have only seen them go bad when the engine has run low of coolant and overheating has taken place. I saw a report on this forum where coolant was leaking out because there was a crack in the engine somewhere.

I read of a case where the engine was overheating because the radiator was covered in mud after a day of wheeling.

Years ago I had a problem because the radiator was old and was not working properly.

Check your coolant every week. Low coolant is an early warning sign. Another early warning sign is an A/C unit blowing hot air. This happens because the engine is running hotter than normal.

If you detect the problem before the overheating damages the gasket, you should be fine.

If anyone has seen a gasket damaged for any reason other than overheating, please let me know.

 

[bikenutty]

My engine never got hot, or leaked. I've never had to add coolant. No symptoms of overheat, detonation, warning lights or codes. Likely head bolt under/over torqued, broken or thread pulled out of block.

 

[roaniecowpony]

 

[roaniecowpony]

My engine never got hot, or leaked. I've never had to add coolant. No symptoms of overheat, detonation, warning lights or codes. Likely head bolt under/over torqued, broken or thread pulled out of block.

...or maybe just a piss poor design.

 

[Remorseless]

...or maybe just a piss poor design.

TBH, the JK with the pre-PUG engines never had the same head issues. This seems to be something more recent causing separation between head and block and allowing coolant to bypass the gasket, definitely a more recent phenomenon. The MLS gaskets used in the 3.6 are pretty squared away generally. Something's just going screwy with either heads/blocks not being true (warping from overheating or what have you) or not being torqued right to maintain a seal.

 

[roaniecowpony]

TBH, the JK with the pre-PUG engines never had the same head issues. This seems to be something more recent causing separation between head and block and allowing coolant to bypass the gasket, definitely a more recent phenomenon. The MLS gaskets used in the 3.6 are pretty squared away generally. Something's just going screwy with either heads/blocks not being true (warping from overheating or what have you) or not being torqued right to maintain a seal.

The PUG has the higher compression and all the VVT and VVL stuff to increase BMEP, which is what challenges the head gaskets. Then they recommend low octane fuel for it. If it detonates, pressures skyrocket.

 

[Remorseless]

The PUG has the higher compression and all the VVT and VVL stuff to increase BMEP, which is what challenges the head gaskets. Then they recommend low octane fuel for it. If it detonates, pressures skyrocket.

True, but with VVT and VVL they can change timing umpteen different ways to compensate and avoid pre-det. Really just smells like build quality issues, either making the heads/blocks or assembling them.

Sponsored