I gained 2 mpg going to the 5W30. Can't really figure out why though. Switched from
RP 0W20 to Motul 8100 5W30 with OEM filter. Any opinions gladly accepted !
RP 0W20 to Motul 8100 5W30 with OEM filter. Any opinions gladly accepted !
Changed oil from 0W20 to 5W30 and ...
- Thread starter GraybeardQ60
- Start date
Summer gas? Rings sealing better? Friendlier 5W30 oil molecules?
What make and model of vehicle?
As proven in this old Fifth Gear episode, it's all about new vs. old oil
It's clearly because 5w-30 is superior and there's no other reason
Better ring seal.
2020 Infiniti Q60 Twin turbo AWD ~ 425hp
I think you did the right thing going to the 5W-30.... Especially in Texas. Next Summer I'm going to do the same thing with my 5.7 HEMI.... Up from 5W-20.
I'm also going to bump up the oil in my "0W-16 Special" Camry from 0W-30 to 0W-40 for the Summer as well.
I doubt the 5W-30 had anything to do with it. There's not that much friction in the engine to make a 2 mpg difference so for that to be accurate, the oil would have to drop friction into the negatives. The oil would have to be an energy source to cause that to happen.
This is the time of year when we switch from winter to summer gas at the pumps. Summer gas gets better mileage than winter gas. Warmer weather promotes better fuel economy and we're having warmer weather lately. Warmer weather also means higher tire pressure, if they haven't been touched, which reduces rolling resistance. Other weather factors like wind (direction and speed) and rain play a factor. You can also be subconsciously "cheating" it with your driving which isn't a stab at you, it's basic human nature.
The only way to accurately measure the effect of engine friction reduction on fuel economy would be to have the car in a climate controlled building, on a dyno, and held at a steady rpm against a steady load. That's been done and the result is never 2 mpg. A perfect world, best case scenario is ~1% or ~0.3 mpg improvement in a car getting 30 mpg.
This is the time of year when we switch from winter to summer gas at the pumps. Summer gas gets better mileage than winter gas. Warmer weather promotes better fuel economy and we're having warmer weather lately. Warmer weather also means higher tire pressure, if they haven't been touched, which reduces rolling resistance. Other weather factors like wind (direction and speed) and rain play a factor. You can also be subconsciously "cheating" it with your driving which isn't a stab at you, it's basic human nature.
The only way to accurately measure the effect of engine friction reduction on fuel economy would be to have the car in a climate controlled building, on a dyno, and held at a steady rpm against a steady load. That's been done and the result is never 2 mpg. A perfect world, best case scenario is ~1% or ~0.3 mpg improvement in a car getting 30 mpg.
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Zee09
$200 Site Donor 2023
Same thing happened to me three days ago. Got my last free oil change... 0w-30.
Mpgs were stellar... Looked at my onboard psi numbers and the dealership put in 42 psi instead of 32 psi...lol
Apparently the 20" tires take more but I had 18s...
Of course not the same but true...
Mpgs were stellar... Looked at my onboard psi numbers and the dealership put in 42 psi instead of 32 psi...lol
Apparently the 20" tires take more but I had 18s...
Of course not the same but true...
wemay
Site Donor 2023
I'm also switching to a 30 from 20 for the 2023 Sonata. Not for any other reason than I have so much of it on hand. I guess another benefit is it keeps both vehicles on the same oil. In my case at least, i've never noticed an mpg difference attributable to an increase in visc.
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Jackson_Slugger
$50 Site Donor 2022
I too have noted a slight fuel economy gain using 5W-30 Mobil 1 HM over the previous 5W-20, but then I had HPL EC SAE30 in the sump and the oil seemed to have a lot of contaminants in it after 2300 miles. And yes, warmer climate and summer gas are the biggest factors....
What was your methodology for measuring how much fuel was consumed ?
D
Deleted member 89374
If you consistently observe improved fuel economy over a longer period with the new oil and filter, it suggests that the combination is indeed providing positive results for your vehicle. Please keep an eye on your fuel mileage with every fill-up and keep this thread updated.
That’s not possible, physics is physics. And besides, you will never be able to distinguish this change in everyday driving.
Observing something is one thing, but being able to attribute it to a specific variable is an entirely different matter.
Here is a post from someone who knows what he’s talking about. He specifically talking about gasoline, but it applies to your situation as well:
Best Brand of Gasoline
Get all my Premium at Sam's Club. Other places around here are 40-50 cents more expensive than Sam's Club premium, making it well worth driving a couple extra miles to fill it up. Get my 87 wherever it's convenient.
bobistheoilguy.com
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Summer blend fuel.
Very possible. I've done the same thing, and noticed better MPG. I suspect more accurate cam timing control.
Correlation.
But not causality.
There is another factor or two involved.
Key takeaway - using a 5W30 in place of a 0W20 won’t kill your MPG. In fact, given your use pattern, it may not hurt it at all.
But not causality.
There is another factor or two involved.
Key takeaway - using a 5W30 in place of a 0W20 won’t kill your MPG. In fact, given your use pattern, it may not hurt it at all.
