20wt - most fuel economy oriented oil !?

[M6ser]

hello to the forum

this is some of the best forums I have seen!

i could not find a topic to answer very important question, specially for 4 , 5 or maybe even 6 usd per gallon era.

many of the cars today ask for 20 wt oils, is there any way to pick the most fuel economy oriented (on paper, by specs) oil formula availabile today?



AMSOIL 0w20
PU 5-20
Mobil 1 0w20
TOYOTA 0-20
....

my car is a 2011 mazda 6 3.7 l , i'm now at 4200 miles and at 3k i have switched to Pennzoil Ultra 1 qt and 4.5 quarts of yellow conv Pennzoil mix ... I plan to switch to Synthetic at 5-6 K miles - what oil would you recommend that can promote the best FUEL ECO and still protects the engine sufficiently in florida 's heat???
What spec of the oil is the most responsible for helping the FE?

 

[tinmanSC]

Welcome to BITOG!

In general, you can look at the Product Data Sheets (PDS) on the web sites for each oil. That will tell you the starting viscosity at 100 Degrees C. The lower the viscosity, the better the fuel economy. Keep in mind this is 3-way tug-of-war between wear protection vs heat vs fuel economy. But if your car is speced for 5w-20, go for it. All the oil you listed are probably within 1% of each other as far as fuel economy increase is concerned.

 

[M6ser]

great!

thks for answer , got some home work to do reading data sheets

 

[M6ser]

Viscosity, @ 100ºC, cSt (ASTM D445)

Mobil 1 Advanced Fuel Economy 0-20 8.70
PU 5-20 8.41
amsoil 100% syn 0-20 8.70
toyota 0-20 - ???
castrol ultra tit. 0-20 8.25
red line 0-20 8.2

can any other 20WT oil beat it , specailly beat it with a significant diference?

PU considering 26usd per jug is hard to beat considering Florida's heat....

 

[Spockian1]

The HT/HS viscosity (also generally provided on the data sheets, except by BP/Castrol) is more highly correlated with fuel economy than is the kinematic viscosity at 100C.

Oddly, a similar question regarding the mechanisms by which lower viscosity oils actually make the difference that they do was summarily locked a little while ago. It was actually quite a good question. I'd advise watching your step. The mods are, apparently, restless tonight.

 

[JOD]

of the oils you've listed, I think the Toyota would offer the biggest advantages for fuel economy. I also think the difference would be very small among those oils, probably on the order of 1% or less.

The start-up viscosity is less, and according to this , the CoF is less (the 'oem oil' is, I believe, Toyoto's 0W20).

I think the Toyota stuff is great oil, and I'm using it in my Ford, but I think the main advantage is (very) slightly decreased start-up wear. I think the difference in FE among different 0W20 oils is probably going to be negligible. If you can get it at a reasonable price, I'd say it's worth using.

Also, the functional viscosity, or ht/hs of the other oils you've listed is greater than that of the Toyota oil (they range from 2.7-2.8 versus 2.6 for the Toyota), which means the Toyota oil will have less frictional losses than those other oils.

 

[A_Harman]

The minimum allowable HTHS viscosity according to API specs for an Xw20 oil is 2.6, so once you find an oil with that spec, there's no point searching further.

 

[Eddie]

You will never find a difference in the real world of driving.

 

[tig1]

You will never find a difference in the real world of driving.[/quo

Last Dec I switched to Mobil 1 0w20 from Mobil 1 5w20 Extended Protection. We make 2-3 trips a year to Gainesville, Fl. and I always set the on board mileage minder as I enter the interstate here in Illinois and check it at the Gainesville exit. The best I have ever gotten was 32.6 on the trip down. I always run at 2500 RPM witch is 72 MPH, and this time I got 33.6 MPG.

 

[Quattro Pete]

Originally Posted By: tig1
I always run at 2500 RPM witch is 72 MPH, and this time I got 33.6 MPG.

Great. Now do it 10 more times to ensure it wasn't just a fluke.

I'm not saying it wasn't the oil's credit, but this difference is so small, any number of external factors could have caused it just as well.

 

[virginoil]

Regardless of the fuel saving offerings a 20 weight can offer, remember to consider what grade of oil does the vehicle manufacturer recommend under specific operating conditions.

 

[M6ser]

great answers, Pennzoil Ultra 5w20 seems like the best overall value than and i will stick with it...

I'm in Flordia's heat and Pennzoil Ultra just seems like a great oil protecting from heat and providing great FE

1 or even few % of improvement (1/2 MPG) may not be worth changing to Toyota stuff due to it's higher buy price and more dificult availability

I think on long highway trips head or tail winds can easly be responsible for few mpg difference... I would make that observation when driving, also amb. temp, and most importantly driving style are all key...

I did drive down i75 once in the winter (150 miles trip) and going south with 15 mph tail wind we got much better mpg than comming back with head wind

 

[Spockian1]

Originally Posted By: Quattro Pete
Great. Now do it 10 more times to ensure it wasn't just a fluke. I'm not saying it wasn't the oil's credit, but this difference is so small, any number of external factors could have caused it just as well.

Absolutely. And thank you so much for the reality check.

The differences... even between 10w40 and 0w20 oil is going to be challenging to quantify, even for people who keep good records. Weather, driving style, mood, traffic, tires, other stuff going on under the hood that you don't know about... all can easily swamp the differences made by the oils.

New tires can hurt fuel economy pretty badly. As they limber up and wear, you get a real improvement from extra flexibility as the tread wears, and an additional 1% or so (fake) boost from how the tire wear affects odometer calibration.

Honda is all gung-ho about 0w20, and even they only estimate a 1.5% improvement from 5w30.

I do use Mobil 1 Advanced Fuel Economy 0w20 in my 1988 Chevy Sprint Metro. And Toyota 0w20 in my Toyota Yaris. And I do believe that it has fuel economy benefits. But I don't imagine that I can prove it from the numbers.

 

[glum]

Originally Posted By: tig1
Last Dec I switched to Mobil 1 0w20 from Mobil 1 5w20 Extended Protection. We make 2-3 trips a year to Gainesville, Fl. and I always set the on board mileage minder as I enter the interstate here in Illinois and check it at the Gainesville exit. The best I have ever gotten was 32.6 on the trip down. I always run at 2500 RPM witch is 72 MPH, and this time I got 33.6 MPG.

Last week I took a 700-mile trip from NC to NY. I don't use the on-board computer to calculate MPG; I calculate it myself using fueleconomy.gov. Each 700-mile trip went through exactly two 3/4 tankfuls of gas (I refill when it gets to 1/4 tank).

On the first tank of gas going to NY, I got 32.0 MPG. On the second (refilling in the middle of the trip), 28.9. On the way back to NC, I got 28.1 and 28.4. I did not pull over and change my oil. My tires did not lose 5 PSI. All this driving was essentially 100% highway. I cannot account for the wild variations, unless (1) the gas pumps were reporting gas volumes that were way off; and/or (2) my preferred gas station here in NC doesn't have ethanol--but I doubt that very much.

 

[tig1]

Originally Posted By: Quattro Pete
Originally Posted By: tig1
I always run at 2500 RPM witch is 72 MPH, and this time I got 33.6 MPG.

Great. Now do it 10 more times to ensure it wasn't just a fluke.

I'm not saying it wasn't the oil's credit, but this difference is so small, any number of external factors could have caused it just as well.


I have heard that before and we will be making that trip many times in the future. Also 1 MPG is 17 more miles to the tank I never got before on this trip. Also this is just over a 3% increase which is what M1 estimates their Mobil 1 Advanced Fuel Economy oils will give back to the average user. I'll gladly take it for just changing oil to a differant wt. oil without loss of protection to the engine. Umh! Now where can I pick up another 3%?

 

[Pesca]

Originally Posted By: tig1
Umh! Now where can I pick up another 3%?


Inflate your tires to the sidewall tires pressure. Myself, I keep a 3 psi matgin, so 42 psi instead of the 45 psi mark.

Decrease your highway speed to 65 mph.

Use cruise control only on flat land.

Do some road edging instead of driving in the groove like others.

If you want more, you will move in some illegal territories, so I only do the above.

 

[tig1]

Originally Posted By: Pesca
Originally Posted By: tig1
Umh! Now where can I pick up another 3%?


Inflate your tires to the sidewall tires pressure. Myself, I keep a 3 psi matgin, so 42 psi instead of the 45 psi mark.

Decrease your highway speed to 65 mph.

Use cruise control only on flat land.

Do some road edging instead of driving in the groove like others.

If you want more, you will move in some illegal territories, so I only do the above.


I won't infate my tires to that kind of pressure because of the ride quality loss and the likely loss of tire wear.

As for running 65 MPH, that's danderous when most of the traffic is doing 75-80.

When using the cruse I usually gas the pedal manually just before entering a sizeable hill to prevent the transmission from downshifting.

 

[Pop_Rivit]

Originally Posted By: tig1

You will never find a difference in the real world of driving.[/quo

Last Dec I switched to Mobil 1 0w20 from Mobil 1 5w20 Extended Protection. We make 2-3 trips a year to Gainesville, Fl. and I always set the on board mileage minder as I enter the interstate here in Illinois and check it at the Gainesville exit. The best I have ever gotten was 32.6 on the trip down. I always run at 2500 RPM witch is 72 MPH, and this time I got 33.6 MPG.


I can see a larger difference that that in average mileage just because of a slight headwind, tailwind or spending a little more time in the draft of a truck (waiting to pass).

That being said, I've never seen any significant increase or decrease from a brand or minor viscosity change in oil.

 

[Smokescreen]

If it hasn't already been said, driver habits/attitude contribute over 90% to better fuel economy, without those learned behaviors no oil, aero mods, tire inflating etc etc will make a difference.

See cleanmpg.com, and ecomodder.com for details

 

[Pesca]

Originally Posted By: tig1
I won't infate my tires to that kind of pressure because of the ride quality loss and the likely loss of tire wear.


I agree with the first part of the sentence (that is a choice I made), but the second part is not true, quite the contrary.

You will get more miles out of overinflated tires than following car manufacturers recommendations.
Like you said, they choose these pressures for comfort, not durability.

Thankfully, my Rogue is quite compliant with high pressure tires. On the other hand, the 2006 Honda Civic sedan would not let you increase tire pressure by a few psis: Miserable ride making you believed you broke something. My wife even went back to the dealer who remove some air and everything went back to normal.