There should be negligible difference in those 2 options. It may be interesting to note that 0w-20 Rotella Gas Truck & SUV has a slightly higher flash point than the equivalent 5w-20. However, I would assume, in general, the 5w-20 to be just a spec better shear stability than the 0w-20. The Rotella Gas & Truck was promoted for High Temperature towing so it should be a solid option.
0w20 vs 5w20 in hot weather
- Thread starter rlabutis
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True. However, the difference between an oil with a 5W winter rating and one with a 0W winter rating will only be apparent at about -35, so the statement is hardly being made in ignorance. In warm weather “like in Florida” there is truly no difference whatsoever.
The ignorance goes both ways, people really need to understand and learn with the winter rating means, and equally important what it does not mean. Probably the #1 most misunderstood topic on this board, right behind thick vs. thin.
The ambient temp difference in FL vs. say MN is so minimal in the scheme of your oil's operating temperature range/properties. The HTHS of the 30W is more than the 20W and in that regard, it's protecting your engine more but that is independent of whether it's 75 out or 100.
This question has been asked 100's of times on BITOG; seemingly weekly if not more often.
0w or 5w winter multi-grade ratings don't come into play in Florida so you can ignore that basic aspect.
Since you have not mentioned an engine, I will speak in generalities and from experience.
A quality 0w20 such as M1 0W20 EP will likely outperform a lower tier 0W- or 5W 20
Overstressed 4 cylinder engines might benefit from a increase of HTHS by moving to a 30 grade lubricant
such as a quality synthetic 5W30 or a preferred 10w30 that may reduce the VM treat. A modest but effective one-step increase in HTHS or KV100 will not compromise an engine - even one with advanced timing and pumping systems - if it is operated in moderate climes. VM used in high VI lubricants are F.E friends but sometimes not particularly "protection" friendly.
The question maybe to ponder now, though one with many differing answers, might be, "which quality lubricant should I choose?" - Ken
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Extra discussion. Many 0w20 have been formulated to a high viscosity index (VI) to provide a somewhat improved warmup regime F.E vs a 5w20 or 5w30. Many demonstrate an appreciably lower kv40 than their 5w brethren. I would call - wrong or right- a commodity grade of this lubricant a fragile lubricant.
Some KV40 (104degF) comparative examples:
Motul VAG 0w20: 38cSt,
Mobil 1AFE 0w20: 45cSt
Mobil Super 0w20: 43cSt - Mobil Super 5w20: 47cSt
Subaru (GF-5) 0w20: 37cSt
Are the VAG and Subaru (idemisu) lubricants above fragile? No, But they are demonstrably and substantially less viscous.
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I’ve noticed this. 0w20 in my hemi cooled off from 226 to 213 very very quickly vs 0w40 took a lot longer.
The question is more like "what oil spec does your car manual specify" so if it is a low saps oil that's required, say, you should be fine picking an oil that is in more or less the same ballpark grade wise depending on weather (warm weather 30 weight is warm weather 30 weight whether 0w 5w or 10w as long as the oil spec is also met).
We are at 100 degrees in Louisiana and running 0w20 Rotella for last 3 oil changes. Seems to like oil or any oil as far as that goes. Uses no oil between changes of one year.
What engine? I'd say a xW-30 oil for a NA engine and a xW-40 for turbo'd.
Pick a grade that is roughly similar if not the same and a weight that’s in the ball park, change at or before the recommended OCI and don’t overthink the rest of it.
Neither one ... step up to 5W-30.
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10w-50 cause this forum looked at a few charts and learned more than companies with multi million dollar R&D departments have figured out in two decades
Is this your little zinger post now?
+1Neither one ... step up to 5W-30.
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Please be aware that the W number is to have nothing to do with the second number "at temperature."
I think that it would be at least understandable that some would think a higher W number would mean a more stable oil in heat a la the "point spread" or even with 10W oils. This appears to no longer be, and may never have been, the case, and probably leads to confusion.
It is the overall formulation that matters.
I think that it would be at least understandable that some would think a higher W number would mean a more stable oil in heat a la the "point spread" or even with 10W oils. This appears to no longer be, and may never have been, the case, and probably leads to confusion.
It is the overall formulation that matters.
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Just applying what I’ve learned from the thicc bois
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