Anyone using an oil other than 0w20?

You are talking some really cold starts. In my climate, my 5W30 will be thinner than oW20 in Canada, so everything is relative. But, there is no question 0W20 is a better solution for most folks.

 

Engines can't read can labels. All the engine knows about your oil viscosity is it's resistance to shear.

5W-30 in Marina this time of year is lower actual viscosity than 0W-20 in Fargo so has less resistance to shear and cranks easier than 0W-20 in Fargo. If you tech is right about the cranking sensitivity, then 0W-20 isn't suitable for cold climates, but we know it is suitable for Fargo this time of year.

 

Exactly the same issues I'd experienced with my car when 5w30 was used.

So it causes the same issues in the warm climate of CA and the cold, wet of the UK.

 

Food for thought. When Honda compared 5W30 to 0W20 they got only 1.5% fuel efficiency improvement. See page 10 here:
http://www.infineum.com/sitecollectiondocuments/notebooks/gf5/J%20Jetter%20Honda%20042109.pdf

That is only 0.75 MPG for Prius. How can you measure that difference?

 

In a Honda I don't know but in a Prius I did

My old fuelly stats show a drop for 2 months when the 'wrong' oil was used. It was the top end mpg's that are affected. With 5w30 it was impossible to get a journey average over 55 mpg, but with 0w20 I can get into the mid 70's mpg again. (using UK mpg's).

Not scientific but maybe Toyota know a thing or two more than Honda on this subject - who sells lots of hybrids and who does

 

I doubt use of 5W30 would bring MPG from over 70s to under 55. 20W50? Possibly.
BTW, 20W50 is approved for Prius use in Australia. Not that I would recommend.

 

I think the point is that Toyota must use their recommended oil in the EPA test cycle, and they want every advantage, even 0.75 MPG. Markets other than the US may have less demanding gas-mileage test programs so Toyota a can recommend a broader range of oils in these markets.

 

Now that's good information. The shop foreman is right on!

 

I have a Jewish manual.
Says you can use other than oW20 if you got a really good deal on it.

 

In my country, TOYOTA only has 10w-40 and filled it on my prius despite what the manual says....

 

that is bad .. .. if you can you should replace ... that oil at least at the next service ... too heavy for the the car ... and you also should contact Toyota ... what your local toyota told you probably bull crap

 

Like I said above, 20W50 if fine for prius in australia. Doubt the car/engine is that much different down there.

 

The Canadian owners manual for my 2010 states "SAE 5W20 OR 0W20 engine oil maybe used. However, SAE 0W20 is the best choice for good fuel economy and good starting in cold weather."

I have used Castrol Syntec 5W20 since the car was new, changed every 8000km. Lowest mileage is about 48 mpg in the cold weather (Imperial gallon) and highest is over 75 mpg, as consistent as the outside temperature year after year. PLUS you can buy Syntec on sale regularly at Walmart for about $25 for a 4.4 litre jug. If I lived on the prairies and I noticed starting issues I might make another choice but I doubt that 0W20 synthetic would flow much differently at -40 than a 5W synthetic.

 

Australian Toyota recommends 5-30 for our conditions. I am getting between 4.6 and 4.8 L/100 kms or 51-49 mpg in mostly rural driving. My best is 4.2 driving purely locally and no freeway driving, sticking to 80 km/h max.

I don't see that there is much difference in conditions between Australia and the southern half of US + California.

 

Motor Oils - Fuel Economy vs. Wear

 

Any discussion about motor oil gets contentious on car forums. Always has, and always will. This does not preclude one from participating, it just means someone is usually quick to disagree. As it pertains to this discussion, Toyota 0w-20 is recommended for optimum fuel efficiency. If one chooses to use a different viscosity or brand, for whatever reason, that means that fuel efficiency will likely be less, if this is the only variable. No quality modern motor oil made for gas cars will hurt the Prius engine if oil/filter change cycles are complied with...Period.

 

I generally do 2 oil changes a year. It will be 0w-20 in the winter and 5w-30 for the summer. We all have our own opinions and as an ex-engine builder, I've developed my own opinions as well.

It's no different than tire pressure discussions. People are quick to point out what Toyota recommends for tire pressure, but forgetting there are literally dozens of different non-OEM tires available and the tire manufacturer can/does make specific recommendations for their particular tire.

 

Just wait til the oil consumption rate reports on Gen III engines starts rolling in with the use of these 0W-20 oils. Very few have 100K miles yet. Toyota is very confident about their usage but I think they have calculated the service life of the car as expendable after 150K miles. Be it a "Green" thing or not, they may regret the recommendation of these extended oil change intervals with the use of light weight oils. We will just have to wait and see. In the mean time, I have elected to change my oil at 5k intervals. For the price of a tank of gas ever 5k,, I think it's a prudent thing to do. Even at that, the use of 0W-20 oil in the hot, So. California climate concerns me. So, that's my opinion.

 

Which mainstream passenger car tire manufacturers make specific pressure recommendations for their passenger car tires that are different from the car manufacturers recommendations?

 

100% agreed on the 5000 mile oil/filter change cycle in principle and practice. However this is going to stir the pot again. Regarding viscosity read the last statement.

http://priuschat.com/attachments/sec_06-01_2010-jpg.44168/