Link: CanadianDriver Auto Tech Auto Tech: Oils that save fuel

Auto Tech: Oils that save fuel
By Jim Kerr

Automobile manufacturers use many methods to improve fuel economy. One that you may not have considered is the use of lighter-viscosity engine oils. Toyota, Honda, Ford, Chrysler, Mazda and Mitsubishi are some of the manufacturers that are specifying the use of 0W-20 synthetic engine oils in some of their vehicles. Toyota has even been using 0W-20 synthetic motor oil as a factory fill in several models since 2006; if your vehicle currently uses 5W-20 conventional oil, then the 0W-20 synthetic oil is an option.

So why would you use 0W-20 oil? First of all, this synthetic oil has excellent stability through a wide temperature range. For example, Mobil1 0W-20 oil pours at temperatures as low as –47 degrees Celsius and protects at oil temperatures as high as 205 degrees Celsius. This is far outside the normal operating range for almost all vehicles.

Vehicles in past decades needed thicker conventional oil with viscosity ratings of 10W-30 or higher. As temperatures went up, the oil would thin out but by having a thicker initial viscosity the oil could still keep moving parts protected. There are many car owners and automotive technicians too who still think you need high viscosity oils to protect engine parts. This may have been true when engine parts were not as precisely made, but now more precise engine parts and the advanced chemistry in 0W-20 oil provides this same protection and has additional benefits as well.

Because 0W-20 flows so well at cold temperatures, it lubricates parts faster during cold starts. Most engine wear occurs during the first couple of minutes after a cold start and fast flowing oil protects sooner; it also allows the engine to crank faster so it can start more quickly. These are real benefits on a cold Canadian winter morning.

Another benefit of 0W20 is reduced internal engine friction, which improves fuel economy in the range of 0.5 to two per cent. This may not seem like much, but improving fuel economy is done in small steps. Every little bit helps and it could save you several hundreds of dollars in fuel costs over the life of the vehicle.

Some of the fuel economy savings result from less power needed to drive the oil pump in the engine – the lighter viscosity oil just flows more easily. Internal engine changes over the years have been made to accommodate thinner viscosity oils. Different oil ring design and roller contact points for the valvetrain reduce a lot of sliding friction.

Engine oil prevents wear by separating moving parts from each other. The oil forms a boundary layer so the parts don’t touch but high spots on the parts can penetrate the oil film and cause wear. More precise tolerances and more accurate machining processes for engine parts help the thinner viscosity oil protect the parts.

0W-20 oil provides the best lubrication under all temperature conditions, reduces engine combustion chamber deposits, reduces vehicle emissions and improves fuel economy. That’s a lot to ask of engine oil, but 0W-20 synthetic is up to the task.

ok. dumb question. ive been using M1 full synthetic 0w-30 since my 2nd oil change at 10k miles. is there a big enough difference between 0w-20 and 0w-30 to care? should i just keep with what i have been doing?

I have been spending a lot of time on BITOG lately... In theory the above article seems pretty good and is true as I understand what I've been reading. I went there to learn about bigger filters for my V6 and kept reading

There are still some advantages, particularly in warmer climates for x-30. The Synthetic 0w-30's are striving for the extended drain certification from the European manufacturers. In the pursuit of the certification the 0w-30's have some very robust additive packages and premium basestocks. To my knowledge the 0w-20's haven't caught on with the Europeans for a variety of reasons and thus the 0w-20's don't benefit from super high-tech chemistry. As for 'tighter tolerances', it's true but overstated IMHO. If you go to Australia 15w-40 goes in petrol-powered 1GR-FE Prado so...

On the other hand; with normal service/intervals and other than desert living 0w-20 would be a great choice. I use 5w-20 at normal intervals. I can't bring myself to go for long intervals so I'm happy. If I lived in Canada I'd be all over the 0w-20 or 0w-30.

Lefty, my point is you may, arguably, be making a better choice with your M1 0w-30.

Just my 2cents,

It is really good info. Thanks.

Here in VA, I use 5w30 synthetic oil year-round in both of my vehicles, as well as my girlfriend's 2002 Highlander V6. It seems to do just fine and since I change it every 3,500 to 4,000 miles....I need not worry about it "thinning out" or losing its protective properties or viscosity. I think that 0-20 would probably be suitable in northern Minnesota or Canada, but not here in the South.

The only exception I know of from "thinner is better" is the oil used in diesel engines. I drive "big rigs" and large straight trucks at work (from 52,000 to 80,000 pounds GVWR); and they are pretty much stuck with 15w40 "compression ignition" motor oil - which can get like Aunt Jemima syrup in the winter time.

Since they run so darn hot -- try pulling 40 tons over a mountain; the higher "thickness" is necessary, although it makes cold starts a real joy in January or February. Even better is when the diesel fuel gels on you. Yuck!


They do make a synthetic for diesels, but it seems as though it might be a wee bit expensive. Try buying 40 quarts at a pop!! That's how large the crankcase is (plus two quarts for the filter) in some of the larger International & Freightliner tractors.

My wife has a Lexus with a 10K oil change interval. It uses synthetic.

In the 2011 4Runner it says to change the oil at 5K. If I run synthetic does that get pushed out to 10?

I realize this is a subjective question, but what have you guys done?

I am an Amsoil fan and like to run synthetic in everything I own that has a motor or needs oil. My 2016 came with synthetic from the factory and also has the 10K oil change interval. Honestly the only way to truly know if you can go 10K or more (Amsoil is rated to 25K with filter change/analysis at 12.5K) is to send your oil off for analysis at regular intervals.

You could goto 7.5K with synthetic at first and change the oil then send it off for analysis...if it's ok push it to 10K and send that oil off. Then send off another 10K example to be sure you can go 10K for the rest of the life of the vehicle. Sounds like a pain but this is the only way to be sure you can goto 10K or more oil change intervals. Also the analysis is very informative and gives you great insight as to how your motor is wearing. Hope this helped.

Check this site for more info.

http://www.blackstone-labs.com/

It's 0w-20 synthetic oil...

I realize the Lexus uses synthetic. The question is if you guys move to synthetic do you change the oil every 5K or 10K?

You're missing the point. 2010~Current 4Runners use a Dual VVTi 2GR-FE variant that specs 0w-20 oil. All 0w-20 oil IS synthetic. The 5k interval is usually recommended for "severe" driving, the normal interval recommended by Toyota for what they consider "normal driving" is 10k. It's all in your owner's manual and maintenance guide.

Yes, I was missing something.

I looked at the 4cyl maintenance schedule.
Thanks, it make sense now.