Switched from 0w-20 to 0w-30 - No change in MPG

[blackman777]

My Honda hybrid was running Mobil 0w-20, then Toyota 0w-20, and then changed to Mobil 0w-30. Folks on the Honda forum swore up and down that I was an "idiot" because the Honda engineers designed the engine for 20 weight & the change to 30 weight will make the MPG fall (and maybe damage the engine too!).

3000 miles later: I see no MPG difference and feel no difference either.

But then the engine caught on fire! Nah just kidding. I really can't tell anything was changed, but I do feel more comfortable running a thicker oil that provides an oil boundary layer. (I like to rev to 6000 a lot.)

 

[demarpaint]

 

[Greg L]

Don't drink the taboo KoolAid....

I used both 0w20 and 0w30 (both Mobil 1) on my 2005 Honda Hybrid....with absolutely no issues. Use either with confidence. (Unless you are still under dealer/factory warranty).


GL

p.s. I had a local oil change service refuse to use anything but 0w20 Honda oil for my car, and they wanted $7.00 per quart to do it.

I said No Thanks, and drove off.

 

[LeakySeals]

 

[kschachn]

K

Originally Posted By: blackman777
My Honda hybrid was running Mobil 0w-20, then Toyota 0w-20, and then changed to Mobil 0w-30. Folks on the Honda forum swore up and down that I was an "idiot" because the Honda engineers designed the engine for 20 weight & the change to 30 weight will make the MPG fall (and maybe damage the engine too!).

3000 miles later: I see no MPG difference and feel no difference either.

But then the engine caught on fire! Nah just kidding. I really can't tell anything was changed, but I do feel more comfortable running a thicker oil that provides an oil boundary layer. (I like to rev to 6000 a lot.)

 

[CATERHAM]

Some people do have some strange ideas about motor oil.

There isn't a huge difference at normal hot operating temp's between M1 0W-20 and 0W-30; just a HTHSV of 0.3cP. The difference will be more compared to TGMO particularly on start-up.
Your engine should still be out of by-pass when the oil is fully hot so there of course will be no harm done.

By the same token you are consuming more fuel whether you can measure the difference or not (who can measure 2%, I can't).
Also you may "feel more comfortable" running the heavier oil but you've gained no additional protection since the spec' 0W-20 already has as much viscosity safety margin that the engine will ever need.

 

[slo town]

Santa Ana, CA, USA

Average January High = 69f/21c
Average January Low = 47f/8c
Average July High = 83f/28c
Average July Low = 63f/17c

Burlington, Ontario, Canada

Average January High = 30f/-1c
Average January Low = 17f/-9c
Average July High = 82f/28c
Average July Low = 62f/17c

Just food for thought,

Scott

 

[blackman777]

It's semi-cold in Burlington ON. (Not news... what was your point?) A 2% loss should have dropped my MPG from 58 to 56.8 on the screen

The 20 weight oil is too thin to provide an oil boundary. I learned that factoid right here, with a chart somebody had posted. Only the ZDDP and other antiwear additives are preventing metal-to-metal contact.

 

[JOD]

weighing feathers on a truckstop scale...

You're not going to be able to reliably measure a 1-3% difference in fuel economy. There are far too many variable at play. Just because the differences are very small, doesn't mean they don't exist.

As far as the thicker oil damaging your engine? Some folks have limited understanding of basic physics. While I think it's completely unnecessary to use a thicker oil, if it "makes you feel better", then use it. It's your car.

 

[CATERHAM]

Originally Posted By: SLO_Town
Santa Ana, CA, USA

Average January High = 69f/21c
Average January Low = 47f/8c
Average July High = 83f/28c
Average July Low = 63f/17c

Burlington, Ontario, Canada

Average January High = 30f/-1c
Average January Low = 17f/-9c
Average July High = 82f/28c
Average July Low = 62f/17c

Just food for thought,

Scott

If you're point is where would I rather spend my winters (and I do like to ski); yes it would be Santa Ana, California.

 

[EType]

 

[kschachn]

I agree with the no change in fuel economy. There's no way on earth you would experience a 2% or even a 1% difference between 0W-20 and 0W-30.

Maybe .02%.

 

[slo town]

I would too if I were you, Caterham!

My point is that it probably doesn't make any difference what the OP runs.

I live in an area that has a 10F hotter July average high than either you or the OP. Even so, with the exception of our Regal GS, our foreign fleet runs on oils on the lighter side of the recommendations.

That said, when I'm blasting 150 miles up the highway at 80MPH at 3,500 RPM - and it's 110f outside - I sometimes think about the fact that the "Toaster" has 0W-20 in it.

Scott

 

[CATERHAM]

Originally Posted By: kschachn
I agree with the no change in fuel economy. There's no way on earth you would experience a 2% or even a 1% difference between 0W-20 and 0W-30.

Maybe .02%.

And you would be wrong.
There is probably a good 4% fuel economy difference between TGMO and M1 AFE 0W-30.

 

[kschachn]

So if I get 30 miles to the gallon I would get 31.2 just by changing the oil?

Why doesn't Toyota (more or less) mandate the use of this oil if it would up their CAFE numbers so dramatically?

And "probably"? Where do you get your numbers from?

Originally Posted By: CATERHAM
Originally Posted By: kschachn
I agree with the no change in fuel economy. There's no way on earth you would experience a 2% or even a 1% difference between 0W-20 and 0W-30.

Maybe .02%.

And you would be wrong.
There is probably a good 4% fuel economy difference between TGMO and M1 AFE 0W-30.

 

[slo town]

Originally Posted By: CATERHAM
Originally Posted By: kschachn
I agree with the no change in fuel economy. There's no way on earth you would experience a 2% or even a 1% difference between 0W-20 and 0W-30.

Maybe .02%.

And you would be wrong.
There is probably a good 4% fuel economy difference between TGMO and M1 AFE 0W-30.


I am inclined to agree. Our Regal GS calls for 5W-30. Instead, I run a German Castrol equivalent, Pentospeed VS 0W-30. This is a much thicker 30W because of its higher HTHS versus the spec'd 5W-30. It cost me 2MPG at a steady 80MPH cruise. On 5W-30 the car would get 28.0 to 28.5. Now it gets 26.0 to 26.5.

I make the same 300 mile round trip regularly, two, sometimes three times a week. Uuugh!

My experience is a repeatable result, unless something went wrong with the car at the time of the oil switch. All I know is that it's not throwing codes so that variable can be eliminated. I check for codes on all our fleet yearly as part of something I call my "annual" (brake bleeding; coolant, gearbox, diff changes, etc are part of my annual). Regularly checking for codes is a routine part of my maintenance.

FWIW,

Scott

 

[InhalingBullets]

I recently switched from M1 0w-20 to GC 0w-30 in my 2007 Toyota Tundra 5.7. I had seen a reply email from Toyota that someone posted suggesting that using a higher grade oil would be warranted based on the operating conditions such as towing or heat. While Toyota didn't spell it out, I live in Texas where it is 100 from early June through September and there are few places on the planet that are highly populated that exceed our high temperatures. I don't exactly know the science behind it but my engine top end is quieter and I will likely continue with GC or even try the Caterham Blend for that reason alone. I also haven't noticed any change in fuel economy. I am no expert at all but it would seem to me that noise in an engine is created by metal to metal contact and reducing said noise could only be beneficial.

 

[kschachn]

I will back off my 0.02% claim but I'd like to see your justification for 4% just going between TGMO and AFE. I used to have a copy of an SAE paper somewhere that discussed this, and IIRC going from something like a 20W-50 to 10W-30 was 1%.

Originally Posted By: CATERHAM
Originally Posted By: kschachn
I agree with the no change in fuel economy. There's no way on earth you would experience a 2% or even a 1% difference between 0W-20 and 0W-30.

Maybe .02%.

And you would be wrong.
There is probably a good 4% fuel economy difference between TGMO and M1 AFE 0W-30.

 

[NMBurb02]

There are a lot of moving part here (no pun intended) so it's hard to make a definitive claim that your oil selection had NO effects on your fuel economy.

First, you did not specific which model or year of Honda you are driving. Let's assume, for the sake of the conversation, unless you want to provide those details, that you are driving a 2013 Honda Civic hybrid, which gets an EPA estimated 44 mpg combined. You stated that you are getting 58 mpg, which is 32% better than the EPA numbers. With your conservative driving style (which is in sharp contrast to your statement about liking "to rev to 6000 a lot") there may not be a lot to gain or lose from a switch in oil viscosity.

Second, we're also talking about a hybrid here, so whatever fuel economy gains you might get from increased efficiency of the ICE is only a part of the overall drivetrain efficiency equation. The 2013 Civic Hybrid's EPA estimate of 44 mpg combined is 37.5% higher than the non-hybrid model with the 1.8L 4 cylinder and 5 speed auto. So the hybrid drive contributes roughly 27% of your fuel economy (everything else being equal).

Third, a lot can change in 3,000 miles due to variations in driving patterns. I have seen more than a 2% change in fuel efficiency over that span. Driving down to San Diego and back with little traffic can make my average fuel economy gauge with 500+ miles on it creep up a good 0.5-1.0 mpg.

 

[NMBurb02]

Originally Posted By: badtlc
It is time for another blackman77 trolling thread. I knew something had been missing lately.

Missing lately? He had one yesterday afternoon and another before this one this morning.