Mobil 1 Supercar 0w40, Amsoil Signature 0w40, Mobil 1 ESP 0w30 in the 2024 Pentastar 3.6, spec'd for 0w20, run its VVL/VVT, just fine.
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5w-30 too thick for modern cars?
- Thread starter 3rdGenGuy
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The resurrection of the dead....
It happens a lot around here.
4wd
$50 site donor 2026
In the absence of MRV etc - might be better than nothing …
Here’s something interesting when you look at pour point and flash point of the 10W-30 …
In very hot climates like Saudi Arabia or Phoenix you go thick all the time using the thickest available. In Saudi Arabia they use 5w40, 10w40 and 15w40.
I use 5w40 all the time summer or winter. Both summer and winter are mild here, but I enjoy the extra protection.
I use 5w40 all the time summer or winter. Both summer and winter are mild here, but I enjoy the extra protection.
Yes, if you are looking at 100C viscosity, HTHS, flash point, shearing tests, NOACK, often a smaller viscosity range conventional oil is tests better than a wider spread synthetic. My theory for stuff that get worked very hard, and not often started in the extreme cold, is to run an oil that wins on those specs, and not worry if its "synthetic" or not. Same with my tractor hydraulic / transmission fluid, regular duratran from petro-canada actually flows pretty decent in the cold, and it should be better at taking the heat/stress of being in a little HST tractor doing its best at big tractor jobs. None of these are regularly started in anything much below -15C, so cold flow isn't really important in that case?
My tractor dealer/diesel mechanic whose been into lots of engines/ equipment put me onto that, just because its "synthetic" doesn't necessarily mean its better for what you are using it for.
So I run 15W40 RT4 in the tractor engine, atv, dirt bikes, all OPE, as they can get worked very hard, and the oil is very cheap in a pail too, so a 10hr OCI's on the dirt bikes without oil filters, is preferable to running a "better" syn for 4 times the cost for twice as long, as it might even shear down faster too!
Shell has started not publishing as many test spec's now so I'm looking to switch, as I need to compare numbers when I chose an oil, not marketing BS or the weasel words around meeting specs without actually getting the accreditation.
4wd
$50 site donor 2026
Yep. Lots of Grp2+ in the mix these days called semi or synthetic …
edyvw
$50 site donor 2026
In -15c you can run literally anything. 15W40 was name if the game in Europe in 90’s. -30? Who cares. Cars parked outside, of course.
4wd
$50 site donor 2026
None - but EHC targets cheap “synthetic” and “semi’ finished lubes …
(Reduce the grp3 percentage and still meet marketing numbers) …
If you drink a cup of coffee and listen closely to each and every sentence this Jason guy says, there is a WEALTH of information to learn about this stuff for a big dummy, ill-informed guy like me. REALLY GOOD STUFF if you are interested in engine oils! Thanks for posting @rstcso !
wemay
Site Donor 2023
All that does is TRY to get THEM out of your warranty period. Oil is not a fix for poor design/QC.
in order to meet dexos 3 ,the base oil can be up to 30% group 2 and rest G3, mix. most blenders use g.3 ,including GTL in some instances. Often times its at the supply on hand and of course blending variances. that's why the SDS have variable amounts on it.
Where have you seen these restrictions for dexos3? Can you post a link? I've never seen a license or approval with base stock requirements, just performance.
Are you running this on wet clutches? I just looked at the certifications and had no idea it was JASO MA/MA2. I like my Ultra1Plus, but it’s way too expensive compared to this.
On the pails I get of 15W40, it does have the JASO-MA rating, but then some specs online don't have it, or other pails don't, but they have a picture of a dirt bike on it? In any case, its certainly not an "energy conserving" motor oil that you must avoid, and many people here run non JASO-MA oils in their street bikes, which have relatively delicate clutches compared to my stuff. I just buy a pail every time its on sale, and it seems that's the rate we use it at. The boys are probably are near 20 oil changes/year on their dirt bikes, as they can put 10 hrs on in a weekend if we don't have something else going on. And the oil does come out looking used! So I'm happier to just change it on these air cooled honda's.
Before BITOG I did run a "energy conserving" oil in my ATV and the clutch did slip, but after a few changes with RT3 it went back to normal.
somewhere on this site? a while ago (with in this past year) but do remember seeing this 30 % amount for the Dexos gen 3.
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While the difference between 0w-20 and 5w-30 at operating temperature is not that great, the difference at environmental temps can be fairly substantial.
I have a 2gr-fks on HPL P+ 0w-30 with no issues, but it behaves more like a 0w-20 than a 5w-30.
My CX-30 starts easier with HPL P+ 0w-30 in cold weather than with the factory fill 5w-30.
I think outright dismissal of anecdotal information is bad. It very well may be that this particular engine under these particular circumstances does prefer 0w-20. It is entirely possible.
I have a 2gr-fks on HPL P+ 0w-30 with no issues, but it behaves more like a 0w-20 than a 5w-30.
My CX-30 starts easier with HPL P+ 0w-30 in cold weather than with the factory fill 5w-30.
I think outright dismissal of anecdotal information is bad. It very well may be that this particular engine under these particular circumstances does prefer 0w-20. It is entirely possible.
I agree. Maybe OP is ascribing the issue to the wrong variable (viscosity), but something clearly changed. I think everyone could be more charitable and try to figure out what caused such a drastic change. Probably just true, true, and unrelated, but you can't blame OP for wondering if it was the viscosity and coming here for help and with a hypothesis, just to get dogpiled.
