3.6 pentastar as bad as it seems ???

That doesn't sound right to me, my half ton doesn't even weigh that much. The GVWR of the rubicon is only 6250 so subtract about 1000 or more off of that to estimate curb weight.
Yeah I think you are right. I know it classifies for the commercial tax break, so maybe that is gvwr, and I believe he had to order it a specific way to reach that.
 
I didn't check all the posts here so ?

Go to youtube and find Pine Hollow Auto Diagnostics, 11 days ago, Just empty every pocket 19 Rubicon pentastar disaster.
Most all lobes wiped out on one of the intake cams, and the part is way out on back order for four months and he would be number 12000 or so the waiting list. There ya go for all the penti fans here.
I guess anyone with this issue should buy a welder and some good grinding wheels, oh and use the hard surface rod like they do on heavy equipment bucket teeth, maybe that will last. :ROFLMAO: :ROFLMAO:
 
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I will say I'm impressed with how my JL on 37s handles our little water trailer, and I'm still running factory 4.10s.

I've got two half tons and a one ton but it's just more fun to get water w the Jeep.

Figure 275 gal water is ~3k plus the 6x10 Snowbear "motorcycle" trailer which I've reinforced is probably at least 800#?

Other than the Pentastar's willingness to get close to redline every time, you don't really know it's there.
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Mopar has went through multiple revisions on the rocker design. Melling beat them to the solution, so you can go with the latest AH revision, or the the Melling. They both are more robust than early production units. You will notice, Mopar has different part numbers for the exhaust side vs intake. Melling has one part because they do the more robust design with all of them. They upgraded the bearing cage with tool steel, increased the size of the roller bearings improving the oil film, improved the oil feed grove geometry to improve oil film at low flow and improved the surface finish, reducing start up friction.

I suspect, that the oil filter housing issue may have a correlation with the rocker failures. Why? Because it is fundamentally an oil film problem and the oil filter housing is more than a holder/cooler. It sits right on the main oil gallery feed and everything downstream (the cams, rockers, lash adjustors, phasers) relies on the stability of oil feed out of the filter housing. Considering how many problems they have had with that unit you can pretty much assume that there have been oiling issues related to oil pressure regulation. There is a built in PRV, filtration bypass behavior, and flow consistency through the passages. They frequently leak so that has profound impact on oil flow and contamination. A leaking oil filter housing can cause aeration of the oil stream, causing oil pressure and flow to drift out of spec. If you have a leaking unit, I recommend not delaying in replacing it and make sure you grab the latest revision. Why not Doorman or other aftermarket? Mopar may be a gaggle of idiots, but after a decade plus of problems using their customers as beta testers, I trust they have been beat over the head by the issue enough to have learned their lesson. The aftermarket companies don't have the level of engineering resources. Not that they have earned that trust but if it is me, I'm buying the latest revision of the Mopar design.

Bottom line, fix the filter housing ASAP when you know it is leaking. If you have an old revision, it isn't unreasonable to take a Saturday and be proactive. If you get the tick, get on it immediately. It will eventually eat your cam lobes, sending metal shavings throughout your engine. Plus, the cams are like $350-$400 each. Use the Mopar filter which is critical to the design of oil flow to the top end of your engine. And of course, use high quality oil of the proper viscosity and change it on a conservative schedule. I'd also consider yearly used oil analysis to catch coolant or Fe spikes, both indicating a likely leak in the oil filter housing. Do those things, and you greatly increase your odds of enjoying your life with the Pentastar.
 
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If you get the tick, get on it immediately. It will eventually eat your cam lobes, sending metal shavings throughout your engine.

I'd also consider yearly used oil analysis to catch coolant or Fe spikes
My experience shows the used oil analysis does not show a spike in FE when the roller bearing fails. The flakes are too large for the ICP to see. The only guaranteed way to see a roller failure is to cut the filter element out flat and look for metal. My filter element went from the usual very small number of flakes to OMG level of flakes. There was zero doubt that something had gone terribly wrong.

I may sound like a broken record, but every single filter element should be cut out of the filter and pulled flat to see what the element has caught. It's a great diagnostic tool, much better than a used oil analysis for detecting an approaching catastrophic failure.

The best part of looking for metal in the filter element is you can catch a bad lifter long before the tapping starts. All of my cams were still in great shape and none needed to be replaced.


Plus, the cams are like $350-$400 each.
I'll fix it for you - $550-$650 for OEM at the dealer, if you can get them without waiting on the national back order.

Link to my post about finding metal in the filter:
https://bobistheoilguy.com/forums/t...al-likely-bad-rocker-chewing-up-a-cam.399622/

Link to my post about replacing the rockers:
https://bobistheoilguy.com/forums/t...tar-after-finding-metal-in-oil-filter.399887/

Used oil analysis showing no increase in Fe:
https://bobistheoilguy.com/forums/t...-000-miles-on-oil-198-000-miles-total.399762/
 
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My experience shows the used oil analysis does not show a spike in FE when the roller bearing fails. The flakes are too large for the ICP to see. The only guaranteed way to see a roller failure is to cut the filter element out flat and look for metal. My filter element went from the usual very small number of flakes to OMG level of flakes. There was zero doubt that something had gone terribly wrong.

I may sound like a broken record, but every single filter element should be cut out of the filter and pulled flat to see what the element has caught. It's a great diagnostic tool, much better than a used oil analysis for detecting an approaching catastrophic failure.

The best part of looking for metal in the filter element is you can catch a bad lifter long before the tapping starts. All of my cams were still in great shape and none needed to be replaced.

This is pretty much it, Inspecting the oil filter will show an abnormal amount of particles caught before the ticking starts. No need for used oil analysis. People clearly don’t understand used oil analysis limitations and put too much faith in them.

As far as cutting the filter open, it’s not really needed, since it’s a cartridge. I just spread the pleats with my fingers and it takes literally few seconds to have a quick look. If something looks abnormal, then I will commit more time to inspect it more thoroughly.
 
I think we got unlucky but I'm still pretty unimpressed. 2015 grand Cherokee with the lifetime warranty. It has had it's timing cover resealed twice and then ate a head gasket around 60k miles last year. Has never been overheated. Noticed the steam at startup so it was caught before it ever lowered the coolant level much. Wife has a friend with a minivan that went through the same. If you google there are quite a few instances of this out there. Sure they made a lot of these engines but we shouldn't have head gasket failure on a unabused low stressed modern engine.

I imagine the oil filter housing will come up soon.

Ironically Hyundai 2.4l in the jeep patriot my brother put 200k on has been great.
 
I would say that is good input. By all means use the simplest method to catch it early. You can catch cross contamination of the coolant with the UOA even if Fe is a lagging indicator.

I may sound like I hate the engine but I think it is a great engine design with a few warts. Keep on top of the known problems and I really like it.
 
I have two 3.6 Litre Pentastars in the family. My wife has a 2016 Chrysler Town & Country that's just had its 70,000 mile comprehensive service, and it runs like a champ. My 2016 Wrangler also runs like it did when I got it. 4-5000 mile oil/filter changes, regular service on transmission and other fluids, and it should keep on running.
 
I have two 3.6 Litre Pentastars in the family. My wife has a 2016 Chrysler Town & Country that's just had its 70,000 mile comprehensive service, and it runs like a champ. My 2016 Wrangler also runs like it did when I got it. 4-5000 mile oil/filter changes, regular service on transmission and other fluids, and it should keep on running.
I believe the Wrangler has the PUG - Pentastar Upgrade Engine with VVL. Apparently they fixed the roller bearing issue on these - and maybe created a follower issue but that its sort of contested / seems not to be as common a problem.

I think the T&C might still have the original version. No idea if they ever upgraded the roller bearings in those but maybe - is a well known issue.
 
I think pentastar is a great engine actually.

Their hybrids caused unbelievable amount of trouble to many. There are good deals to be found, but for a reason
 
I've had multiple 3.6L engines, but my current 2014 T&C (selling on my own because two dealers would not take it on trade or buy it) at 135,000 miles has had a P0302 for 6 months or so, and I not been able to fix it (plugs, rockers, coils, swapped injectors).

I should do a compression check, but there is so much else wrong with the van that it is not worth keeping. After internet sleuthing, I think it has succumbed to the cylinder 2 overheat issue and possibly burned a valve. Is that what happened? I don't know, nor do I care, as the van is broke in other areas too, and I am sick of it.

I do feel like I got my money out of that van, so no big loss, but my 2002 Voyager with a 3.3L went 165,000 and needed nothing more than basic maintenance, and did not use any oil. Rust was what killed that van.

The 3.6L in my 2020 JLU Sport Willys Wrangler purrs like a kitten. I'll decide around 120,000 miles or so if I will keep it longer than that or not when the time comes.
 
I believe the Wrangler has the PUG - Pentastar Upgrade Engine with VVL. Apparently they fixed the roller bearing issue on these - and maybe created a follower issue but that its sort of contested / seems not to be as common a problem.

I think the T&C might still have the original version. No idea if they ever upgraded the roller bearings in those but maybe - is a well known issue.
Both of our Pentastars have the VVT
 
There are two flavors.

1st gen - Variable Valve timing - VVT

2nd Gen pug - VVT + Variable valve lift - VVL.

I am unsure exactly what model got what but they rolled with both apparently for some period of time.
Idk the difference in the valve mechanics, but our 2016 and 2018 ram promasters have their fair share of rocker and cam issues. Not a ton…we see far more of all the other nitpicky problems.
 
I think we got unlucky but I'm still pretty unimpressed. 2015 grand Cherokee with the lifetime warranty. It has had it's timing cover resealed twice and then ate a head gasket around 60k miles last year. Has never been overheated. Noticed the steam at startup so it was caught before it ever lowered the coolant level much. Wife has a friend with a minivan that went through the same. If you google there are quite a few instances of this out there. Sure they made a lot of these engines but we shouldn't have head gasket failure on a unabused low stressed modern engine.

I imagine the oil filter housing will come up soon.

Ironically Hyundai 2.4l in the jeep patriot my brother put 200k on has been great.
Got a 21 Wrangler Rubicon, same issue. Internal leak of head gasket with no overheating. I can see the coolant on the top of the piston with a borescope. I baby this thing even though we drive the wheels off with 109k. I’m here on BITOG, an auto machinist formerly, and an enthusiast so it just doesn’t really have a “good” reason it should have failed.

I suspect either the quality of the head bolts or the quality of assembly at the engine plant. It may have been on the edge of checking out “good” and something moved over time.

I’m going with P1 Manufacturing 3.6 Pentastar cylinder head studs (made in Missouri) not because of needing the material strength(but who knows, right?), but taking it easy on the block side threads and torquing accuracy and consistency. I don’t want to go back in this far to this mess of wires, bolts of various lengths on the same part so you have to document with pictures where each length goes …. gotta be OCD. lol Everything has to come off… it sucks.
 
The Penstars are excellent engines, a lot of horsepower a lot of torque, if you take care of it, it will take care of you
 
Got a 21 Wrangler Rubicon, same issue. Internal leak of head gasket with no overheating. I can see the coolant on the top of the piston with a borescope. I baby this thing even though we drive the wheels off with 109k. I’m here on BITOG, an auto machinist formerly, and an enthusiast so it just doesn’t really have a “good” reason it should have failed.

I suspect either the quality of the head bolts or the quality of assembly at the engine plant. It may have been on the edge of checking out “good” and something moved over time.

I’m going with P1 Manufacturing 3.6 Pentastar cylinder head studs (made in Missouri) not because of needing the material strength(but who knows, right?), but taking it easy on the block side threads and torquing accuracy and consistency. I don’t want to go back in this far to this mess of wires, bolts of various lengths on the same part so you have to document with pictures where each length goes …. gotta be OCD. lol Everything has to come off… it sucks.
How much/rapidly would you say it's leaking? I assume it was coolant loss that made you investigate?
 
Our '17 Wrangler is now at 145,000 miles, so far so good. We had the oil filter housing replaced at about 60,000 miles. I too share concerns about the likelihood of leaks and the possibility of the oil cooler seals leaking and mixing in AF with the motor oil. I think they tried to make the oil filter housing/cooler as compact as possible with hiding it under the intake manifold but it could have been done better with a conventional oil filter and an external oil cooler.
Not really a fan of:
all aluminum engines
open deck block designs
My favorite Jeep engine is the cast iron 4.0 straight six. We have one in a '98 Grand that has 183,000 on it now, bought new.
One day I compared weights of the 4.0 and the 3.6, the 4.0 is more than 100 lbs heavier.
 
Our '17 Wrangler is now at 145,000 miles, so far so good. We had the oil filter housing replaced at about 60,000 miles. I too share concerns about the likelihood of leaks and the possibility of the oil cooler seals leaking and mixing in AF with the motor oil. I think they tried to make the oil filter housing/cooler as compact as possible with hiding it under the intake manifold but it could have been done better with a conventional oil filter and an external oil cooler.
Not really a fan of:
all aluminum engines
open deck block designs
My favorite Jeep engine is the cast iron 4.0 straight six. We have one in a '98 Grand that has 183,000 on it now, bought new.
One day I compared weights of the 4.0 and the 3.6, the 4.0 is more than 100 lbs heavier.
I don't disagree but my buddy has a '98 XJ on 37s with 5.13. He actually stroked the motor to .... 4.2?

My JL is running the same size rubber with factory 4.10 and on highway grades around Moab I can simply walk away from him. It's not even close.

Now, I'm sure he's heavier but honestly, it would hardly matter.

Anyway, the 4.0 is unquestionably durable but the Pentastar has better driveability we've come to expect from modern motors.
 
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