Interesting 3.6 Tear Down.

[talljeeper]

I found this commentary to be really informative. The motor is a little dated for Gladiator purposes, but the narrative is really informative. I cant imagine being a service tech and having to do this kind of crap on a daily basis. I picked up on his comments on commonly known issues with the current 3.6 as well as his comment on oil viscosity. I hope you enjoy, its worth the watch.

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[NVjeff]

Thanks for posting that.
I hate the complexity of these engines but I know it's necessary for the the power and economy, which I enjoy.

 

[ShadowsPapa]

Had to laugh - he's obviously not worked on that many engines since the 1990s, and these specifically.
He griped about plastic vacuum lines saying rubber lines were superior. Proof he's no mechanic.
The industry switched to the plastic lines decades ago because they are superior to rubber lines.
Rubber either dries and cracks and splits, or it "rots" due to the petrol fumes, or even direct contact with oil or gas. I've replaced hundreds of yards of rubber vacuum lines over the years but have yet to see a plastic line crack like he griped about. Sure, if it's 20 degrees out and you pull and bend plastic, it might crack, but I used the plastic vacuum and fuel lines from a 1994 ZJ in my 82 SX4 when I did the 4.0 transplant - and those lines were perfect. They were as good as when they came from the factory. Those plastic lines he said are inferior have over 135,000 miles and 30 years on them and they are fine. In fact, they are pretty resistant to cracking.
I just had a feeling he was all about complaining about the engine, and not so much knowledge on it. He even talked in the beginning about "roller" running against those shot lobes. There's no roller there.

I had to stop after a few minutes. IMO, sorry, too much trash talk without really understanding what he was seeing.

 

[talljeeper]

Had to laugh - he's obviously not worked on that many engines since the 1990s, and these specifically.
He griped about plastic vacuum lines saying rubber lines were superior. Proof he's no mechanic.
The industry switched to the plastic lines decades ago because they are superior to rubber lines.
Rubber either dries and cracks and splits, or it "rots" due to the petrol fumes, or even direct contact with oil or gas. I've replaced hundreds of yards of rubber vacuum lines over the years but have yet to see a plastic line crack like he griped about. Sure, if it's 20 degrees out and you pull and bend plastic, it might crack, but I used the plastic vacuum and fuel lines from a 1994 ZJ in my 82 SX4 when I did the 4.0 transplant - and those lines were perfect. They were as good as when they came from the factory. Those plastic lines he said are inferior have over 135,000 miles and 30 years on them and they are fine. In fact, they are pretty resistant to cracking.
I just had a feeling he was all about complaining about the engine, and not so much knowledge on it. He even talked in the beginning about "roller" running against those shot lobes. There's no roller there.

I had to stop after a few minutes. IMO, sorry, too much trash talk without really understanding what he was seeing.

Dang Papa, who crapped in your Wheaties this morning? LOL. Papa you should fire up a YouTube channel. This guy seems fairly knowledgeable. I enjoyed the tear down and I can agree to disagree with some of his observations and agree with some of yours as well. However some of his observations were absolutely spot on. My intent was to provide a visual tear down on the 3.6 and the complexity of how every part on these engines have an interdependence. Ending your viewing early you missed some good stuff I am pretty he has been inside more engines than you and I combined ...or not HAHAHHAA

https://www.youtube.com/@speedkar99/videos

 

[Lunentucker]

And THAT is why I use Blackstone Labs at every oil change. Obviously, if the cams are being destroyed by the rollers there is going to be an inordinate amount of metal in the oil.

 

[ShadowsPapa]

And THAT is why I use Blackstone Labs at every oil change. Obviously, if the cams are being destroyed by the rollers there is going to be an inordinate amount of metal in the oil.

Here's the part that runs on the cam being talked about in that video's first several minutes -

?

Worse than a roller - it's a rubbing part more like the lifters in a cam-in-block egine........ but the same result, yeah, if there's metal wear even only to the point it can be barely seen or measured, it will show up in oil samples.

This guy seems fairly knowledgeable. I enjoyed the tear down

My thinking is that he's more outside of the realm of working on ordinary production vehicles in a shop where you see all the rotted vacuum hoses and how the plastic lines last forever, and that there are no rollers on that parts of the Pentastar.
It was as if he hadn't seen some of those methods or materials before - even though common for years. Why Pentastar engines fail - just like any other, a multitude of reasons.
It felt like he started with a fair dislike of the engine and picked apart every bit of it he saw (at least as far as I got).
Comments below on plastic parts were totally amazing - I guess none of them had worked on production vehicles -
Chevy LS, Toyota, or Mercedes intake manifolds, for example?

Likely a great performance engine builder, but he really missed some things as well.

 

[Teqsand]

Thanks for posting that.
I hate the complexity of these engines but I know it's necessary for the the power and economy, which I enjoy.

3.6 pentastar and power/economy do not belong in the same sentence

 

[Stan H]

I think he has a disdain for 0-20 oil. In my opinion he was right about ine thing the inordinate amount of slug in the oil pan was from lack of oil changes. I wished we could use 5w-20 in these engines. But truly if the film strength of the oil is strong then 0w-20 will be fine. OW-20 is used simply because of the VVT not because of the bearings. What he doesn't know and we don't either is what you may be looking at is not only a lack of oil changes. But in fact a engine in which the owner decided heybIm using 10w30 or 5w-20 or even 5w-50 . I use Amsoil 0W-20 Signature series and change it far below the amount of miles they say you can go. As a matter of fact. I change my filters 2 times for every one oil change. Oil is the life of the engine. Pure and simple. The tear down I have watched several times. Some of which does not come off during the cam and lifter changes ..ie lower intake and fuel rails. But nevertheless it was watchable. In the 21 model year the lifters where redesigned. And as a matter of fact the old style lifters can not be purchased and are discontinued and have been replaced with the new design which hold up better. I have 86000 on mine and it's still going and I stay out of the GO pedal as much as possible. Okay here goes. I have this belief that constant high end ragging of any engine will lead to premature wear. I used to be a cop and the engines were ragged out in a year or 2 from constant high end use.

 

[ShadowsPapa]

In the 21 model year the lifters where redesigned. And as a matter of fact the old style lifters can not be purchased and are discontinued and have been replaced with the new design which hold up better.

Are you referring to the lash adjusters?
The 2020 JT 3.6 had cam/follower issues, the 2021 and later not so much.
If they changed the lash adjusters, maybe they were finding that the lash adjuster didn't keep up with the switching between low and high lift modes where they'd need to move each time there was a transition between high and low. If a lash adjuster stuck, things could get hammered to death.
There was a lot of speculation as to the cause of the 2020 JT cam issues - cam hardening, and so on.
Also, the exhaust lash adjuster is responsible for lubricating the followers. There was talk of perhaps issues there as well.

I think he has a disdain for 0-20 oil. In my opinion he was right about ine thing the inordinate amount of slug in the oil pan was from lack of oil changes. I wished we could use 5w-20 in these engines.

I detected disdain for a number of things - the engine itself, superior plastic vacuum lines, the cam solenoids (his "VW comment) and more.
The difference between 0w20 and 5w20 will be cold weather and since so many actually overlap in viscosities, there's pretty much no gain going to a 5w vs a 0w. Oil A at the 5w could be the same as oil B at 0w.
5w20 would simply be maybe a bit thicker in colder weather. 0w20 would possible "flow a bit better" in very cold temperatures, but a minimal difference. Once warmed up, you won't care.

The engine in question appears to have had any of these combinations -
short, infrequent runs - sitting a lot,
never getting up to temperature to boil out the moisture and preventing acid and sludge formation,
lack of oil changes
Short drives are hard as heck on engines.
People griping about FORM on the 4xe are likely some of the same people who abuse a full gas vehicle by their short runs, bragging about their short commute, and then not compensating by doing more frequent oil changes.
To an extent - the shorter the drives, the lower the speeds combined with short drives, the more frequently you need to change oil.
These jeeps actually track that!

 

[NVjeff]

3.6 pentastar and power/economy do not belong in the same sentence

It's miles better than the 258 I'm used to in the CJ's.
I have no personal experience with the 4.0 but I'm told the 3.6 makes better power, and I know it gets better economy.

I was disappointed when Jeep stopped using an inline 6 engine however I quickly came to appreciate the 3.6 in my '13 Rubicon.

I don't know what engine would be better as far as economy, power and would fit the JK, JL or JT.

 

[ShadowsPapa]

It's miles better than the 258 I'm used to in the CJ's.
I have no personal experience with the 4.0 but I'm told the 3.6 makes better power, and I know it gets better economy.

I was disappointed when Jeep stopped using an inline 6 engine however I quickly came to appreciate the 3.6 in my '13 Rubicon.

I don't know what engine would be better as far as economy, power and would fit the JK, JL or JT.

Lots of experiences with the 258 and 4.0 (as well as prior versions of the I6, the 232 and 199)
I had multiple cars with the 258 and all were trouble-free engine-wise.
My 82 had a 258 that was abused (beat, not good care, few oil changes by the prior owner) and even it went 160,000 miles.
I had a 77 AMX with the 258 and drove it all over the place for several years.
But the 3.6 is a much more efficient engine.
Take proper care of them and they'll go the distance. There's a lot of 'em out there without problems.

 

[Hootbro]

It's miles better than the 258 I'm used to in the CJ's.
I have no personal experience with the 4.0 but I'm told the 3.6 makes better power, and I know it gets better economy.

I was disappointed when Jeep stopped using an inline 6 engine however I quickly came to appreciate the 3.6 in my '13 Rubicon.

I don't know what engine would be better as far as economy, power and would fit the JK, JL or JT.

It's all relative. Remembering the anemic engines of years past, the Pentastar 3.6 is plenty. There is always going to be the "more power" crowd regardless of what they come with.

 

[Stan H]

Are you referring to the lash adjusters?
The 2020 JT 3.6 had cam/follower issues, the 2021 and later not so much.
If they changed the lash adjusters, maybe they were finding that the lash adjuster didn't keep up with the switching between low and high lift modes where they'd need to move each time there was a transition between high and low. If a lash adjuster stuck, things could get hammered to death.
There was a lot of speculation as to the cause of the 2020 JT cam issues - cam hardening, and so on.
Also, the exhaust lash adjuster is responsible for lubricating the followers. There was talk of perhaps issues there as well.



I detected disdain for a number of things - the engine itself, superior plastic vacuum lines, the cam solenoids (his "VW comment) and more.
The difference between 0w20 and 5w20 will be cold weather and since so many actually overlap in viscosities, there's pretty much no gain going to a 5w vs a 0w. Oil A at the 5w could be the same as oil B at 0w.
5w20 would simply be maybe a bit thicker in colder weather. 0w20 would possible "flow a bit better" in very cold temperatures, but a minimal difference. Once warmed up, you won't care.

The engine in question appears to have had any of these combinations -
short, infrequent runs - sitting a lot,
never getting up to temperature to boil out the moisture and preventing acid and sludge formation,
lack of oil changes
Short drives are hard as heck on engines.
People griping about FORM on the 4xe are likely some of the same people who abuse a full gas vehicle by their short runs, bragging about their short commute, and then not compensating by doing more frequent oil changes.
To an extent - the shorter the drives, the lower the speeds combined with short drives, the more frequently you need to change oil.
These jeeps actually track that!

Yes cam followers sorry.

 

[Stan H]

Are you referring to the lash adjusters?
The 2020 JT 3.6 had cam/follower issues, the 2021 and later not so much.
If they changed the lash adjusters, maybe they were finding that the lash adjuster didn't keep up with the switching between low and high lift modes where they'd need to move each time there was a transition between high and low. If a lash adjuster stuck, things could get hammered to death.
There was a lot of speculation as to the cause of the 2020 JT cam issues - cam hardening, and so on.
Also, the exhaust lash adjuster is responsible for lubricating the followers. There was talk of perhaps issues there as well.



I detected disdain for a number of things - the engine itself, superior plastic vacuum lines, the cam solenoids (his "VW comment) and more.
The difference between 0w20 and 5w20 will be cold weather and since so many actually overlap in viscosities, there's pretty much no gain going to a 5w vs a 0w. Oil A at the 5w could be the same as oil B at 0w.
5w20 would simply be maybe a bit thicker in colder weather. 0w20 would possible "flow a bit better" in very cold temperatures, but a minimal difference. Once warmed up, you won't care.

The engine in question appears to have had any of these combinations -
short, infrequent runs - sitting a lot,
never getting up to temperature to boil out the moisture and preventing acid and sludge formation,
lack of oil changes
Short drives are hard as heck on engines.
People griping about FORM on the 4xe are likely some of the same people who abuse a full gas vehicle by their short runs, bragging about their short commute, and then not compensating by doing more frequent oil changes.
To an extent - the shorter the drives, the lower the speeds combined with short drives, the more frequently you need to change oil.
These jeeps actually track that!

I have to drive mine for work and typically put 2000-2500 a month on it. I hate it but have no other choice right now. During the time I dont run it it will be sitting for the majority of 2 weeks with maybe a couple 30bmile trips in there for my personal use or trips to the gun range etc.. the only thing that grips me is I would love to know exactly why Jeep say 0W-20 in these (other than because of the VVT) this 2 stage pump really puts out the oil regularly reaching 79 & 80 pounds when I do have to get on it. Which isn't that often. I'm older now and this Jeep truck is never going away. I intend on rebuilding it when the time comes. Entire driveline each as they fail. Up until that time I will change oil often. I actually my front and rearends are due again. I used Amsoil full sythetic 75-90 in them at 40k or 41k and I already rolled up another 40k+ so next time I'm off thats getting done also. Plus I just bought the fluid for the tranny and filter. Gonna have the dealer do the transmission oil change .

 

[Lunentucker]

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