OIL, 0-20 or otherwise (couldn't find the other oil threads)

[DrewsJT]

Interesting that they’re doing a 0W-40. I’ve only seen that on my euro cars. I figured it would be 5W-30, which I do think about switching to on my 2020 now that it’s out of powertrain warranty.

0w-?? Are the same weight oil, they only differ at high temps.

Interesting that they’re doing a 0W-40. I’ve only seen that on my euro cars. I figured it would be 5W-30, which I do think about switching to on my 2020 now that it’s out of powertrain warranty.

Oil weights refer to the viscosity of motor oil, which indicates how thick or thin the oil is at different temperatures. The numbers on oil labels, such as 5W-30, show how the oil performs in cold conditions (the first number) and at normal operating temperatures (the second number).

castrol.com
Ow-?? At startup temp, the only difference is at operating temp.
I'm changing the both my jeeps to 0w-40

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[Hootbro]

The thing is they already got the "mileage " rating when certified, I don't believe it effects Cafe now after the consumer takes possession. But I could be mistaken

They still have to certify the EPA estimates on the Monroney Label as being accurate for what is being delivered.

 

[ShadowsPapa]

Ow-?? At startup temp, the only difference is at operating temp.
I'm changing the both my jeeps to 0w-40

Why?

 

[DrewsJT]

Why?

For the same reason GM did it. It doesn't lube enough IMHO that's a major reason for rocker/lifter failure

 

[ShadowsPapa]

For the same reason GM did it. It doesn't lube enough IMHO that's a major reason for rocker/lifter failure

I guess you missed their reasoning and as it was pointed out in the video - they did it as a bandaid to compensate for a crappy crankshaft journal finish. Rougher finish requires a heavier oil "wedge" to keep the bearing and journal apart. Had they put the proper finish on the crankshafts, the original oil would be fine. It's to protect the bottom end.

It's not that it "doesn't lube enough" - it's because GM was running sandpaper against the bearings and needed a heavier wedge.
For 2025, the oil remains as it was - no changes - because the crankshaft has the proper, correct finish.
"doesn't lube enough" - that isn't really an issue. They needed a less lossy oil in the bearing journals. They lube the same. The problem for GM was that the normal oil was getting out of the rod and main journal areas faster than a heavier oil would and allowing the rough surface mountain peaks to make contact with the bearings.
IF they had correctly manufactured those crankshafts - 21-24 only, by the way, are what's involved - not before and not after - they could have kept using the same oil without issue.

Yeah, people are watching that video and coming to the wrong conclusions.

 

[KevinC]

So do you think 0w20 penzoil ultra plat is ok or go to pennz plat 0w30 ty in advance Nick

Use what the owners manual tells you.

 

[ShadowsPapa]

Use what the owners manual tells you.

Always have, always will. I guess it comes from knowing what I know, instead of buying into hype and uneducated guess and speculation.

 

[DrewsJT]

I guess you missed their reasoning and as it was pointed out in the video - they did it as a bandaid to compensate for a crappy crankshaft journal finish. Rougher finish requires a heavier oil "wedge" to keep the bearing and journal apart. Had they put the proper finish on the crankshafts, the original oil would be fine. It's to protect the bottom end.

It's not that it "doesn't lube enough" - it's because GM was running sandpaper against the bearings and needed a heavier wedge.
For 2025, the oil remains as it was - no changes - because the crankshaft has the proper, correct finish.
"doesn't lube enough" - that isn't really an issue. They needed a less lossy oil in the bearing journals. They lube the same. The problem for GM was that the normal oil was getting out of the rod and main journal areas faster than a heavier oil would and allowing the rough surface mountain peaks to make contact with the bearings.
IF they had correctly manufactured those crankshafts - 21-24 only, by the way, are what's involved - not before and not after - they could have kept using the same oil without issue.

Yeah, people are watching that video and coming to the wrong conclusions.

What's your explanation for lifter/canshaft failures in Stalantis/Ford/GM/Toyota?
What have they ALL changed other than the operating temp side of the oil for economy?

 

[DrewsJT]

I guess you missed their reasoning and as it was pointed out in the video - they did it as a bandaid to compensate for a crappy crankshaft journal finish. Rougher finish requires a heavier oil "wedge" to keep the bearing and journal apart. Had they put the proper finish on the crankshafts, the original oil would be fine. It's to protect the bottom end.

It's not that it "doesn't lube enough" - it's because GM was running sandpaper against the bearings and needed a heavier wedge.
For 2025, the oil remains as it was - no changes - because the crankshaft has the proper, correct finish.
"doesn't lube enough" - that isn't really an issue. They needed a less lossy oil in the bearing journals. They lube the same. The problem for GM was that the normal oil was getting out of the rod and main journal areas faster than a heavier oil would and allowing the rough surface mountain peaks to make contact with the bearings.
IF they had correctly manufactured those crankshafts - 21-24 only, by the way, are what's involved - not before and not after - they could have kept using the same oil without issue.

Yeah, people are watching that video and coming to the wrong conclusions.

I didn't miss it, I choose to do it because I believe all the manufacturers have compromised longevity for fuel economy.

 

[Splenda]

So do you think 0w20 penzoil ultra plat is ok or go to pennz plat 0w30 ty in advance Nick

I think 0w20 is fine, but I also think 0w30 is fine. If I drove lots of highway miles and long trips, I would use 0w30. My Gladiator rarely gets all the way up to operating temperature. My commute is 8 miles each way, 4 miles through town and 4 miles on a country road. I use 0w20 because most of my driving is done with the engine warning up.

 

[Blizzard]

Ok, serious question. What changed in the pentastar 3.6 to move from 5w30 to 0w20? I mean this isn't a new design or new engine... so... why did it change?

 

[Hootbro]

Ok, serious question. What changed in the pentastar 3.6 to move from 5w30 to 0w20? I mean this isn't a new design or new engine... so... why did it change?

There was a generation change of the Pentastar called the PSU/PUG that rolled out in 2017 that called out out the now 0W-20. IIRC, included a newer two stage valve lift followers, revised lower block and windage tray and a few other things. Prior gen had VVT and ours has VVL valvetrain.

Few references I have found shown the connecting rod and crank clearances the same but supposedly the VVL system was designed around the 20WT oils for optimal performance.

 

[Stan H]

I didn't miss it, I choose to do it because I believe all the manufacturers have compromised longevity for fuel economy.

If you got 100k out of an engine in the 70's and 80's you was doing great . I seen a couple 318's do 200k . Longevity wise I think bottom end of modern engines hold up well but what is a weaker point is the top end . Lots more valves lots more EPA specs to meet which changed alot of stuff to make them run more efficiently. 0W-20 makes sense so long as you change it. To me that is the key to success.

 

[WK2JT]

I guess you missed their reasoning and as it was pointed out in the video - they did it as a bandaid to compensate for a crappy crankshaft journal finish. Rougher finish requires a heavier oil "wedge" to keep the bearing and journal apart. Had they put the proper finish on the crankshafts, the original oil would be fine. It's to protect the bottom end.

It's not that it "doesn't lube enough" - it's because GM was running sandpaper against the bearings and needed a heavier wedge.
For 2025, the oil remains as it was - no changes - because the crankshaft has the proper, correct finish.
"doesn't lube enough" - that isn't really an issue. They needed a less lossy oil in the bearing journals. They lube the same. The problem for GM was that the normal oil was getting out of the rod and main journal areas faster than a heavier oil would and allowing the rough surface mountain peaks to make contact with the bearings.
IF they had correctly manufactured those crankshafts - 21-24 only, by the way, are what's involved - not before and not after - they could have kept using the same oil without issue.

Yeah, people are watching that video and coming to the wrong conclusions.

It’s been a minute since I’ve seen any speculation on the exact cause of the 3.6 cam failures. If it was a crappy finish, it would seem a heavier weight oil would help, similar to the GM issue. Based on my limited oil weight experimentation and UOA, that doesn’t seem likely.

The other causes I’ve seen thrown around are adjuster bearing failure, faulty hardening, or lack of oiling. In those situations, oil weight shouldn’t make a bit of difference, right?

Ultimately, it’d be nice to know the root cause because for some, like hardening, could be resolved. Others like oiling maybe not so much. In the end, I’m just curious how likely I am to replace the cam again.

 

[johnnyreno]

We Always ran 0/30 in 15 rubicon runs like new in fact better than new with 200k 0/20 is to thin its about the sound to a common sense approach. Way to thin here in Texas. Tomato Tomoto 21 gladi likes it. Good luck all

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