3.6 Cam Self destruction

[DC3]

Curious, what about using the 5W-30 oil made you discontinue it and go back to 0W-20?

I replaced my judgement with the factory manual guidance?

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[DC3]

If you let me know when your doing it, I will rebuild it asap while your there

Is it weird for me to say you are my hero!!!! ?

 

[donaldus]

How often are those of you with wear problems changing your oil and are you adding modifiers? I don’t rat my 3.6 Sport S, change the oil every 3K, add Archoil and Zmax. So far, very quiet. Banks intake, throttle body spacer, MBRP exhaust, and Pedal Commander.

 

[@californiajeeping]

factory spec... 0w20. Mobil 1 full synthetic

For the first couple oil changes ~12k miles, I took it to the dealer (wave). After the dealer, I used 5w30 until the first cam episode ~15k miles and then used 0w20 afterwards.

OIl changes at 6k intervals through dealer and 5k on my dime

I ran 5-30 and mine still ticked and ate cams. It had multiple misfires at high rpm. Dealers wanted me on the hook for the tear down so I traded it in. Went for the diesel and it’s amazing.

 

[ShadowsPapa]

How often are those of you with wear problems changing your oil and are you adding modifiers? I don’t rat my 3.6 Sport S, change the oil every 3K, add Archoil and Zmax. So far, very quiet. Banks intake, throttle body spacer, MBRP exhaust, and Pedal Commander.

It's been proven by an engineer (and the oil companies) that additives usually reduce the wear protection of oil, not improve it. Oils are formulated with the additives blended using science and too often adding things later actually changes the chemistry in negative ways. Oils have been tested and then additives added and tested again and the protection actually went down in almost every case.

Hundreds of thousands use the recommended oils and have no issues at all - so there's no way to prove that doing any different avoided a disaster.
It would be like someone saying "I went 100,000 miles and changed oil every 6,000 miles and never used an additive" as proof of something.


Quotes from the web:

The vast majority of the oils tested here, were tested just as they come, right out of the bottle. But, there are also some oils tested with aftermarket additives put in them. These additive tests were for informational purposes only, and are not generally recommended. Because aftermarket additives can ruin an oil’s carefully formulated original additive package, aside from what it may or may not do for its wear protection capability. It is always best to choose a good performing oil in the first place, that does not need any help.


Most major oil companies say to NEVER EVER add anything to their oils, because doing so will upset the oil’s carefully balanced additive package that was designed by their Chemical Engineers. I tested doing that very thing in several different oils, and found that adding zinc additives in every case, ruined the oils by SIGNIFICANTLY REDUCING their wear protection capability. That of course, is just the opposite of what people “think” they will be getting. So, those major oil Companies were absolutely correct about not adding anything to their oil.


If an oil "needs" an "additive", it's time to switch to a better oil.

 

[donaldus]

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[donaldus]

I’ll continue additives…still drive the 74 VW I purchased new; 3k oil change + additives…never had an engine problem with any vehicle over 60 + years of use. Do what makes you comfortable; Jay Leno uses Archoil, he probably has more engines than you. I can find ANY number of pros/con statements on the web…including bigfoot and alien sightings.

 

[ShadowsPapa]

LOL - yeah, Jay Leno takes every one of them out and flogs them daily, too..... (he also gets paid to use certain products)
I bet I've worked on more than he owns.

I agree, do what you want, but using marketing to prove something, or Jay Leno?
I've never had an engine problem in over 50 years, either. Only one was where the prior owner abused it - and that one went 160,000 miles (and is still going in another car after new bearings and an oil pump)
So I guess we prove nothing.

 

[WK2JT]

LOL - yeah, Jay Leno takes every one of them out and flogs them daily, too..... (he also gets paid to use certain products)
I bet I've worked on more than he owns.

I agree, do what you want, but using marketing to prove something, or Jay Leno?
I've never had an engine problem in over 50 years, either. Only one was where the prior owner abused it - and that one went 160,000 miles (and is still going in another car after new bearings and an oil pump)
So I guess we prove nothing.

My 3.6 has the cold start top end chatter for approximately the first 1/2 mile. After that, it purrs even when getting into the revs. I believe you’ve mentioned yours does it too. Perhaps your first JT? I’m curious if this is just typical cold engine top end chatter, had other engines do this also, or a precursor to the cam issue? I’ve thought about trying an additive to see if it helps with this particular issue. I know the manual says to not use additives. Even if it did address this particular issue, not sure if it could protect against the cam issue. Would be ideal to understand the root cause of the cam issue.

 

[ShadowsPapa]

My 3.6 has the cold start top end chatter for approximately the first 1/2 mile. After that, it purrs even when getting into the revs. I believe you’ve mentioned yours does it too. Perhaps your first JT? I’m curious if this is just typical cold engine top end chatter, had other engines do this also, or a precursor to the cam issue? I’ve thought about trying an additive to see if it helps with this particular issue. I know the manual says to not use additives. Even if it did address this particular issue, not sure if it could protect against the cam issue. Would be ideal to understand the root cause of the cam issue.

My second one - the 2022, is basically like the first - the 2020. A little cold start valve noise, then it quiets down after a few moments.
I've lost track of the number of Grand Cherokees we've had with the 3.6 Probably 4, maybe 5, as my wife likes to trade often although she always says "this is the last one".
The valve train is less quiet when first started cold, but after that, on all of them, it's quieted down to the point it is no worse than anything else I've owned. Many I6s have a fair amount of valve train noise. This is no worse, and actually better than some.
Both my wife and I have actually exited our Jeeps and realized we forgot to shut them off they run pretty quiet.

Sometimes I wonder how much of what I hear is injector and how much is valve train. But nothing to this point (make sure I get that part in!) has sounded out of the ordinary.
There's going to be some more noise to these because of the way the intake follower works. On low lift mode the high lift part is basically just following it's profile on the cam held there only by spring pressure - is some of the noise associated with how the high lift portion operates?
There's a certain amount of "lash" when the high lift portion is locked by the pin - there's clearance there according to the tech training docs. And there has to be or when hot the pin could never lock that portion.

 

[WK2JT]

My second one - the 2022, is basically like the first - the 2020. A little cold start valve noise, then it quiets down after a few moments.
I've lost track of the number of Grand Cherokees we've had with the 3.6 Probably 4, maybe 5, as my wife likes to trade often although she always says "this is the last one".
The valve train is less quiet when first started cold, but after that, on all of them, it's quieted down to the point it is no worse than anything else I've owned. Many I6s have a fair amount of valve train noise. This is no worse, and actually better than some.
Both my wife and I have actually exited our Jeeps and realized we forgot to shut them off they run pretty quiet.

Sometimes I wonder how much of what I hear is injector and how much is valve train. But nothing to this point (make sure I get that part in!) has sounded out of the ordinary.
There's going to be some more noise to these because of the way the intake follower works. On low lift mode the high lift part is basically just following it's profile on the cam held there only by spring pressure - is some of the noise associated with how the high lift portion operates?
There's a certain amount of "lash" when the high lift portion is locked by the pin - there's clearance there according to the tech training docs. And there has to be or when hot the pin could never lock that portion.

Agreed on the I6. My two 3 series BMW’s were loud on cold start. I probably wouldn’t have given the 3.6 cold start noise a second thought if not for some experiencing this cam issue. I’ve always thought I would just drop a V8 in it if the engine does go South. Now with the hurricrate announcement, we may have a second option that is likely to cost less than the V8. Of course, the 3.6 in mine will probably go 300k and I’ll never find out. Lol

 

[ShadowsPapa]

Agreed on the I6. My two 3 series BMW’s were loud on cold start. I probably wouldn’t have given the 3.6 cold start noise a second thought if not for some experiencing this cam issue. I’ve always thought I would just drop a V8 in it if the engine does go South. Now with the hurricrate announcement, we may have a second option that is likely to cost less than the V8. Of course, the 3.6 in mine will probably go 300k and I’ll never find out. Lol

Thinking along the same lines -if mine does take a dump and it's beyond warranty or for some reason it's not covered, I'm drooling over the thought of that new I6 engine sitting in my JT.

I'm sure I'll never have the pleasure, though. Looks like the same transmission that's behind the 3.0 diesel would work behind that hurricrate engine.

 

[DC3]

I ran 5-30 and mine still ticked and ate cams. It had multiple misfires at high rpm. Dealers wanted me on the hook for the tear down so I traded it in. Went for the diesel and it’s amazing.

I am in the same boat, the Diesel is amazing!!! With the GDE I am running 32 - 33psi and it is a rocket. I should be good until the fuel pump grenades

 

[Tommyd]

factory spec... 0w20. Mobil 1 full synthetic

For the first couple oil changes ~12k miles, I took it to the dealer (wave). After the dealer, I used 5w30 until the first cam episode ~15k miles and then used 0w20 afterwards.

OIl changes at 6k intervals through dealer and 5k on my dime

So why did you switch back to 0w20? You think that had something to do with it?

 

[Barnaby’sdad]

I have wondered if this engine simply wants to be abused once in a while...Its a shitty way to build a motor but driving it like you stole it might have some merit.

Yup. I haven’t seen a CEL since I started getting on it and stopped driving it like an old lady

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