5.7 HEMI preventative care, which flavor of 5w20

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2,209
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WA
Re: vvt slow response code with thicker oil.

iirc, I had read that oil viscosity grade (obviously within reason and talking about 20 vs. 30 or 40) has no impact on vvt operation ... Is there a documented case that viscosity diff between a 20 and 40 can cause issues after warm-up? as both oils are very viscous when cold. or is it the sludge that causing the code?

just curious since I'm using 30 instead of 20 and was kind of even considering a light 40 but haven't pulled the trigger yet.
 
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21
Location
Texas
Re: vvt slow response code with thicker oil.

iirc, I had read that oil viscosity grade (obviously within reason and talking about 20 vs. 30 or 40) has no impact on vvt operation ... Is there a documented case that viscosity diff between a 20 and 40 can cause issues after warm-up? as both oils are very viscous when cold. or is it the sludge that causing the code?

just curious since I'm using 30 instead of 20 and was kind of even considering a light 40 but haven't pulled the trigger yet.
It’s come up on the Challenger forums a few times, I would say it’s not common. I did see it personally on a Pentastar v6, but thats a pretty different VVT system (more complex with 4 phasers vs one). The VvT still works, it’s just that it may not respond as fast as the OBD self-monitoring software is expecting. If I were concerned that my drive cycle was too much for a 20-weight (and it would take a lot to convnice me it’s an issue) I wouldn’t hesitate to try it. The phasers can’t smash valves with a stock cam, so theoretically the worst thing that would happen is an error code, which can be cleared and then shouldn’t come back if you go back to 20-wt oil.
 
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17,061
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Upper Midwest
It’s come up on the Challenger forums a few times, I would say it’s not common. I did see it personally on a Pentastar v6, but thats a pretty different VVT system (more complex with 4 phasers vs one). The VvT still works, it’s just that it may not respond as fast as the OBD self-monitoring software is expecting. If I were concerned that my drive cycle was too much for a 20-weight (and it would take a lot to convnice me it’s an issue) I wouldn’t hesitate to try it. The phasers can’t smash valves with a stock cam, so theoretically the worst thing that would happen is an error code, which can be cleared and then shouldn’t come back if you go back to 20-wt oil.
All of which of course is not necessary, it’s only to enforce the CAFE requirements. It’s completely unnecessary to design the VVT actuators in that way.
 

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45,842
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Ontario, Canada
If the problem is not enough oi,l no matter what oil is run the problem of not enough oil will still be there.
If it was not enough oil they'd all fail. Since they don't, it clearly isn't. Based on the posts from an FCA tech in another thread it definitely points to a materials/supplier issue, same as with GM's AFM lifter debacle.
 
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21
Location
Texas
All of which of course is not necessary, it’s only to enforce the CAFE requirements. It’s completely unnecessary to design the VVT actuators in that way.
Its not even the actuators... its the tolerance in the software that turns on the error code is unnecessarily tight. And *that* may partially be driven by emissions, although VCT/VVT actually is more of a performance thing than an emissions thing.
 

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Its not even the actuators... its the tolerance in the software that turns on the error code is unnecessarily tight. And *that* may partially be driven by emissions, although VCT/VVT actually is more of a performance thing than an emissions thing.

Yup, the software tracks both oil temperature and pressure and if those two things get out of whack with anticipated values it triggers the code. I expect this is almost entirely, if not entirely, done to ensure the proper spec oil is used so that folks aren't using 15w-40 mixed-fleet in them.
 
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227
Location
Noblesville, IN
0w40 is fine for mds they use it in the 6.4 hemis with out issue. I think the thin oil for valve timing stuff was just early thinking that it needed to be so thin to work.

0w40 is still relatively thin oil in the grand scheme of things. Not a concern unless you think you are going to have a warranty battle over a silly MS spec oil use that is basically a spec that means (this is our current contract oil) it’s not some hard spec like vw 508, 504, MB 229.5, Porsche a40 etc
 
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8,575
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Texas
It is my opinion that to enhance the Hemi engine's lifespan use 5w/30. I use 5w/30 Syn in my Hemi RAM Limited and Grand Cherokee with the 3.6L. 88k miles on the RAM and 126k on the Jeep...trouble free.
 
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13,024
Location
Indiana
I don't have to tell you why, if don't wish to look don't and it was response to LevelZero post or was that forgotten.

Dont be a cupcake.

The thing you posted shows nothing.

With the time it took for you to think of a reply, you could have simply filled him in. Also, the forum has a “reply” function, which for some reason, you chose not to use. Very misleading post.
 
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1,886
Location
Indiana
Dont be a cupcake.

The thing you posted shows nothing.

With the time it took for you to think of a reply, you could have simply filled him in. Also, the forum has a “reply” function, which for some reason, you chose not to use. Very misleading post.
He seems to be a one hit wonder pushing Amsoil in numerous threads.
 
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15,884
Location
N.H, U.S.A.
So I'm sure we all know the history of 5 7 Hemi's having needle bearings seize and freeze the rollers, causing lifter failure and grinding down the cam. There are 2 reasons thst I've found that are blamed for the failure. 1. Is that the design of the motor doesn't get enough oil to the lifters or the camshaft at or below ~1500rpm. 2. ...
For reference, I do a ~5000 mile OCI with either a Wix or Fram Ultra. My driving is mostly in-town short trips (<15mi) and semi-rural state routes (35-40 miles at 50ish MPH) i don't do a ton of highway time.
And living in New England, ill only use synthetic because -15 degree starts suck
We just did any many page thread on this subject about a month ago; but I suppose it need more flushing out. LZ, We dont get that many -15 deg starts up here. Your short tripping is a bit of a problem. I would run an imported "REAL" synthetic that wont varnish as much. I dont know what that oil would be in the ACEA realm. VW/ Audi Porsce 0W20 would be too thin as the HTHS is too low. But, you cant fix design/parts issue with oil.
Roller lifter Torrington bearings dont care about ZDP either, they need a good oil supply to keep them cool when they are spun up.

Buy an extended service contract on the engine for 1500 bucks and hope it trashes at 80K mile - then you'll get a fresh motor after 5 or 6 years :)
 
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