Can thicker oil prevent rocker arm failures in Pentastar 3.6 V6?

I have never claimed in any discussion that any oil or change in viscosity is going to "fix" a mechanical design issue. Think we all pretty much agree there.

Also, concerning the late 90s and early 2000s, I'd say the oils back then were not as robust as they are today. Could be many people who had issues were partly caused by how they treated and maintained those vehicles....
True but we are talking about the SJ era of when oils are now moving to Group II from solvent dewaxing...
 
Review a few different PDS docs from a few different manufacturers and you can find your answer.

I already know the answer. Just like many 5W-20's may actually utilize a thicker base oil than many 5W-30's, because they don't have to balance everything by adding VII's to match a finished 30W...
 
I would trust Toyota engineers more than the Chrysler engineers. For most people it's better to stick with manufacturer's recommendations but Chrysler had 10 years to perfect the Pentastar but still they haven't made Pentastar flawless. When GM and Chrysler changed to 0W20, there were engine failures, may be it's due to AFM/MDS but in pentastar there is no MDS but the hypothesis here is people who used 5w30 and frequent OCI in pentastar had less rocker failures.
Oh, I wouldn't. They've had their share of issues, too.
 
Oh, I wouldn't. They've had their share of issues, too.

They do. I think the overall Toyota "fit-and-finish" is better but they have had their share of **** shows. Even engines many consider bulletproof like the 1.8L that powered the older Corollas often develop a drinking problem if not anally maintained, and thicker oil only makes it worse...
 
Just curious, to those of us with the newer designed PUG motor that was designed and calls for 0w20 worldwide, are you still thinking we would be going to a thicker oil for it?
I would not. Read up on it. It was designed from the start with 0w20 in mind. Of all the JL's and JT's in the Jeep clubs I frequent, not a single member has complained of an issue and I'd say nearly all of them run the specified 0w20. BUT, I doubt you'd do any harm with 5w30. Some 5w30's aren't much thicker than some 20 weights, really. But for me, I'm sticking with what was recommended. Especially since my 3.8, which I think originally was designed with 5w30 spec has gone 171k mostly on 20 weight oil with no issue. Runs like new.

Read up on what @OIL_UDDER has said about this very subject. I'd bet he'd tell you to stick with 0w20 in this engine. He's got a Pentastar (Pre-PUG) with some mileage on it, too. I'd ask him what he runs in his. After all, he designed it.

You thick oil guys will go into an orgasmic state over this one: My best friend has a Pentastar which gets special treatment. It is a 2012 and probably has between 110k and 130k on it by now. I'll have to ask him. But he runs 5 quarts of 5w20 along with 1 quart of Lucas Heavy Duty Oil Stabilizer, which has a viscosity at 212 degrees of 110. (Yikes!) with no additives. I think he's flat nuts but the thing runs fine, so far. He bought the Jeep used, so it hasn't had this diet the whole time. He generally goes by the OLM for changes, but frequently goes well past the point where it indicates change time. I'd guess he's got about 40k on it while adding this stuff. He'd laugh his arse off over us debating a 20w vs a 30w.

I'm not sure how he got onto that Lucas crap, but I think he got the idea when he had a Tahoe with a Chevy 350 where he went several years without changing the oil, but only adding. It started smoking pretty badly so he added the Lucas and swears it helped it run a couple more years until it finally siezed up.

He can't be convinced to do it any other way, so I observe with extreme curiosity.
 
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I would not. Read up on it. It was designed from the start with 0w20 in mind. Of all the JL's and JT's in the Jeep clubs I frequent, not a single member has complained of an issue and I'd say nearly all of them run the specified 0w20. BUT, I doubt you'd do any harm with 5w30. Some 5w30's aren't much thicker than some 20 weights, really. But for me, I'm sticking with what was recommended. Especially since my 3.8, which I think originally was designed with 5w30 spec has gone 171k mostly on 20 weight oil with no issue. Runs like new.

Read up on what @OIL_UDDER has said about this very subject. I'd bet he'd tell you to stick with 0w20 in this engine. He's got a Pentastar (Pre-PUG) with some mileage on it, too. I'd ask him what he runs in his. After all, he designed it.

You thick oil guys will go into an orgasmic state over this one: My best friend has a Pentastar which gets special treatment. It is a 2012 and probably has between 110k and 130k on it by now. I'll have to ask him. But he runs 5 quarts of 5w20 along with 1 quart of Lucas Heavy Duty Oil Stabilizer, which has a viscosity at 212 degrees of 110. (Yikes!) with no additives. I think he's flat nuts but the thing runs fine, so far. He bought the Jeep used, so it hasn't had this diet the whole time. He generally goes by the OLM for changes, but frequently goes well past the point where it indicates change time. I'd guess he's got about 40k on it while adding this stuff. He'd laugh his arse off over us debating a 20w vs a 30w.

I'm not sure how he got onto that Lucas crap, but I think he got the idea when he had a Tahoe with a Chevy 350 where he went several years without changing the oil, but only adding. It started smoking pretty badly so he added the Lucas and swears it helped it run a couple more years until it finally siezed up.

He can't be convinced to do it any other way, so I observe with extreme curiosity.
I would not. Read up on it. It was designed from the start with 0w20 in mind. Of all the JL's and JT's in the Jeep clubs I frequent, not a single member has complained of an issue and I'd say nearly all of them run the specified 0w20. BUT, I doubt you'd do any harm with 5w30. Some 5w30's aren't much thicker than some 20 weights, really. But for me, I'm sticking with what was recommended. Especially since my 3.8, which I think originally was designed with 5w30 spec has gone 171k mostly on 20 weight oil with no issue. Runs like new.

Read up on what @OIL_UDDER has said about this very subject. I'd bet he'd tell you to stick with 0w20 in this engine. He's got a Pentastar (Pre-PUG) with some mileage on it, too. I'd ask him what he runs in his. After all, he designed it.

You thick oil guys will go into an orgasmic state over this one: My best friend has a Pentastar which gets special treatment. It is a 2012 and probably has between 110k and 130k on it by now. I'll have to ask him. But he runs 5 quarts of 5w20 along with 1 quart of Lucas Heavy Duty Oil Stabilizer, which has a viscosity at 212 degrees of 110. (Yikes!) with no additives. I think he's flat nuts but the thing runs fine, so far. He bought the Jeep used, so it hasn't had this diet the whole time. He generally goes by the OLM for changes, but frequently goes well past the point where it indicates change time. I'd guess he's got about 40k on it while adding this stuff. He'd laugh his arse off over us debating a 20w vs a 30w.

I'm not sure how he got onto that Lucas crap, but I think he got the idea when he had a Tahoe with a Chevy 350 where he went several years without changing the oil, but only adding. It started smoking pretty badly so he added the Lucas and swears it helped it run a couple more years until it finally siezed up.

He can't be convinced to do it any other way, so I observe with extreme curiosity.
From my research on here, I run it with Mobil 1 EP 0w20. And feel pretty comfortable using that. Just get mixed signals sometimes on here reading up on it all lol
 
One would think that with the hemi and 3.6 valvetrain problems Chrysler has forgotten how to make a reliable valvetrain components.
To have forgotten implies Chrysler ever knew how to make reliable valve train components in the first place.
 
I have seen 240°F+ in mine--plenty of reasons that could happen and operating conditions is not the least of it. I am not trying to sell or convince anyone to run a certain viscosity oil.

Everyone can run whatever they want, but at the same time, no one can deny the laws of physics (unless they are oblivious to them or just chooses to refuse to believe them). xW-30 affords more protection than xW-20, plain and simple.
So if it’s the oil weight that keeps an engine alive and not the tolerances and technology, how do Pro Stock engines run 10,000 RPM on 0W-2 oil?
Pro Stock breakdown
 
So if it’s the oil weight that keeps an engine alive and not the tolerances and technology, how do Pro Stock engines run 10,000 RPM on 0W-2 oil?
Pro Stock breakdown
Let's see:

1. I never said the oil was "keeping the engine alive' nor did I say anywhere that xW-20 was not adequate. I simply said that I wanted extra protection by using a higher viscosity oil.
2. For some here, it is apparent the laws of physics only exist in the realm of science fiction.
3. I am not a "thickie" by any stretch of the imagination having run xW-20 longer than most here have ever dared to--15K+ miles on a single OCI.
4. Since we are now comparing hand-built engines that can cost more than 40x that of the mass-produced engine in my Jeep and are rebuilt countless times before the engine in my Jeep would ever come close to needing it, I don't know @SubieRubyRoo, since you broached the subject, why don't you explain it to all of us how it is possible.
 
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There's a guy on here that said he helped design the 3.6. He claims the heads need good flow and insinuated to me the specs 20 was best. I dunno. I run a thick 5w20 hm in ours. 102k, runs fine so far knock on wood.

ZeeOsix's thoughts on low rpm moft does have me wondering though. My wife drives slow and at low rpms, and the 62te in the van likes to shift early.
 
For most people it's better to stick with manufacturer's recommendations but Chrysler had 10 years to perfect the Pentastar but still they haven't made Pentastar flawless.
In what way do you think the pentastar is “flawed”?
And if it’s a flawed motor why are you buying a ram?

Oh and what year is this “slightly used” ram again? I didn’t see that mentioned.
 
Seems it is more of a engineering failure. Every car manufacturer has them but some manufacturers are quick to modify. Mazda had an issue with it’s 2016 Miata manual transmission. They went through 5 revisions and completely reversed reliability by 2019. The guys with the earlier models were blaming thin oil and sticking 140 weight gear oil in. Mazda were replacing bad MT’s free to the failures. Like putting a band aid on a broken arm with thicker oil. It is up to Chrysler to reverse the trend.
 
In what way do you think the pentastar is “flawed”?
And if it’s a flawed motor why are you buying a ram?

Oh and what year is this “slightly used” ram again? I didn’t see that mentioned.
It is a 2020 Ram, I want a NA V6 engine, Ram is with in my budget. I said it is flawed because of the rocker failures and oil cooler leaks, my reasoning is with a 5w30 oil may be the rocker failures can be reduced also by not over torquing oil filter may be oil cooler may last longer. Pentastar is flawed but it is a decent engine with a combination of good power, mileage and reliability.
 
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