Ow20 v 5w30

Years ago one of the engineers for the chrysler v6 team… maybe the 3.3/3.8 designers(?) wrote a blurb on allpar. he noted that lighter oils did a better job of protecting the valvetrains, while heavier oils did better on timing chains and bottom end. The only solid conclusion I took was timing chains go hydrodynamic at lower rpm’s with heavier oils. That’s a good thing. On my vehicles with chains, I go one grade heavier.
 
Sure it does, for cold starts. As one who has experienced the real struggles of bitter cold operations in Alaskan winters, cold startup can be a real problem. Especially with the wrong oil adding to the issues.

If it’s -30 outside but the engine is at operating temperature, the ambient temp has no real effect on the performance of the oil. The oil temperature is what matters.
 
At -10C either a 0W or a 5W winter rated oil will perform the same. There's no guarantee that at that temperature either one would have superior cranking performance and pumpability.
 
My 2019 Nissan Pathfinder and 2022 Nissan Frontier both recommend 0w20 per Nissan. I've run synthetic 5w30 in both with no noticeable effect on cold start, performance, economy, noise, etc. Who knows if one will allow the engine to last longer.
 
If it’s -30 outside but the engine is at operating temperature, the ambient temp has no real effect on the performance of the oil. The oil temperature is what matters.
Oil temperature is not well regulated like coolant temperature is. Ambient temperature makes a big difference to oil temperature. Even on a car like mine with an oil-to-coolant heat exchanger, steady state oil temperatures will be 80 C at -35 C ambient, and 100 C at 35 C ambient. The difference in viscosity at these two temperatures is about the same as the difference between a 0W20 and a 5W40. In vehicles without an oil cooler, the difference in oil temperature would be even larger.
 
Agreed, but a 0W is good for the cold starts in the winter temperatures we experience here.

I recommended the OP stick with a 0w20 for his situation.

Oil temperature is not well regulated like coolant temperature is. Ambient temperature makes a big difference to oil temperature. Even on a car like mine with an oil-to-coolant heat exchanger, steady state oil temperatures will be 80 C at -35 C ambient, and 100 C at 35 C ambient. The difference in viscosity at these two temperatures is about the same as the difference between a 0W20 and a 5W40. In vehicles without an oil cooler, the difference in oil temperature would be even larger.

That is true in older vehicles. In newer vehicles, especially newer turbocharged ones with modern oil coolers, oil temps stay pretty consistent unless you are really hammering on them. Both of our vehicles stay in the same 6-8° window under normal driving conditions. Again, OP with a hybrid, I do not suspect this vehicle will ever see engine oil temperatures in excess of ~220°F in any weather.
 
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At -10C either a 0W or a 5W winter rated oil will perform the same. There's no guarantee that at that temperature either one would have superior cranking performance and pumpability.
This where I always get confused. If both perform the same at this cold of a temp, why does 0W-20 even exist? I believe it is only for the fuel mileage benefit but since they are both a 20 grade at operating temp, the fuel mileage benefit must be realized at the time of a cold start and the initial warm-up period. If that benefit is in fact realized, wouldn't that mean that the 0W-20 is less vicious and is allowing the engine to operate easier and therefore use less fuel and isn't that a good thing? When manufacturers are making their miles per gallon claim, how and at what temperature do they measure it?
 
This where I always get confused. If both perform the same at this cold of a temp, why does 0W-20 even exist? I believe it is only for the fuel mileage benefit but since they are both a 20 grade at operating temp, the fuel mileage benefit must be realized at the time of a cold start and the initial warm-up period. If that benefit is in fact realized, wouldn't that mean that the 0W-20 is less vicious and is allowing the engine to operate easier and therefore use less fuel and isn't that a good thing? When manufacturers are making their miles per gallon claim, how and at what temperature do they measure it?
Well any oil that gains a 0W performance rating will perform the same as another oil with the same rating, within the tolerances of the requirement. Above the temperature of the test there is no guarantee that any oil with a 0W rating will be thinner or thicker than one with a 5W rating.

Fuel economy during start and warmup is not as important as quickly reaching operating temperature. All oil is very viscous at low temperatures, so you want to get out of there as soon as possible. Thicker oil warms up faster as well so this may have something to do with it. Automakers are more concerned with emissions at low temperatures then they are with fuel economy so fast warm-up is essential.

I'd also say that since only one oil can be recommended in the owner's manual per the CAFE award letter requirements, an automaker would be cautious about recommending one with a 5W rating since there are areas where a 0W rating would be needed (or at least desirable).
 
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Hi folks. The owners manual on my my 23 Elantra 1.6hybrid says the oil should be 0w20 BUT it also says consider using 5w30 with warmer temps (the image looks to like they identify anything above 5c as ‘warmer’. it says 0w20 is better for fuel economy. The oil fill cap says use 0w20.
I live in Toronto … should I just stick to 0w20 all year or fill with 5w30 for the summer months? Or is it wash either way and I’m just overthinking this?
Google this: HTHS wear graph.
I prefer to use a 5W-30 all year round as it has higher HTHS and more MOFT film thickness.
 
It's a shame you have an inability to express yourself without using asterisk-producing language. Your sentence structure needs improvement as well.
Oh thanks. Hows the bay area smelling these days, still like cat pee? I dont know how to type all that good, but I know not to live in a place that smells like cat pee and burning sugar. And of course, void of most liberal snowflakes
 
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