Oil

0-20 is only made in synthetic as far as I know. I know it is expensive but that is what you should use. There are other threads on this and some helpful hints on where to purchase. I think Walmart has it pretty cheap.

Also have you seen that the oil change on the Prius is a little more difficult than a standard old change?

G

 

The manual specifically calls for 0W20. It's currently only available as synthetic, in other words, the manual calls for synthetic 0W20. It also says you may use the other oil for -one change- but you MUST switch back to 0W20 after that.

That's pretty plain english. I don't know what you're asking about! Find the 0W20 at Walmart.

There is another thread on this. Don't remember the title.

 

"MUST switch back to 0W20".

So the use of 5W-20 oil is going to destroy the engine?

Somehow I don't think so. Could somebody with a more intimate knowledge of the details for this forced switcharoo, please tell us why it is mandatory? No doubt it will affect the MPG, but other than that, what else?

 

Because your engine is turning off and on frequently, you need 0W20 synthetic oil. You will have nearly zero wear on the engine at 200,000 miles with synthetic oil. I change my own oil and use Mobile 1 across the entire fleet. My cars are worth more to the next owner because I have used Mobile 1 from day one. I'm now using the new Mobile 1 0W30 in my other cars instead of 5W30. The zero has to do with temperature on the low side so folks who live in cold climates the oil is not so gooey at start up. Also, thin oil clings to metal longer. Also, it is easier for oil filters to do their job with synthetic oil. I think I paid $6.27 a quart at Walmart for Mobile 1 0W20. Mercedes requires Mobile 1 0W40, which is getting easier to find but only comes in quarts, as does 0W20 for the moment. The last benefit is that synthetic oil can take more heat for a longer period of time than conventional oil. The OEM's believe in so much they are installing synthetic oil at the factory. Unless I had a really old car, I would not use anything other than top-notch synthetic oil.

 

Don't you get fewer miles per gallon in cold weather? Oil might have something to do with that or they would be using 5W20 instead of 0W20. Toyota wants that oil to be supple in cold conditions.

 

"Supple" it most certainly sounds to be, since I have read that flushing oil is 0W-20 rated, with the consistency of water.
That sounds pretty thin to me, but I just assume Toyota have done their homework and development testing with respect to engine lubrication using this grade.
If it really does reduce engine wear, I would have thought that less frequent oil changes would be possible, say every 10,000 miles rather than the 5K currently quoted.

 

Ron, on most cars you can have longer intervals between changes. My Mercedes SLK is 10,000. The Corvette has an oil change light that comes on and that is about 10,000 miles also although both cars have an electronic notification when it is time to change the oil. In our Suzuki, I change the oil at 7,500 miles and I could go to 10,000. That is one of the benefits of Synthetic oil is that it works longer than conventional oil primarily because it can take the heat and not lose its viscosity. Why Toyota chose 5,000 is beyond me. Maybe because of heat. Does anyone know the operating temperature of the engine?

 

2010 Prius III with Navi.

I have used Mobil 1 synthetic motor oil since the mid 90's, the first time being on my 1994 Honda Civic (VX) model.

I changed at 7,500 miles with filter. I remeber adjusting valves at about 140,000 miles.

I could not believe how clean the valve cover and valve train looked. That made me a believer.

Our Prius is going to use 0X20 Mobil 1, best price is Walmart. They also may be getting 5 quart containers of 0x20 for a possible price of about $23.00.

Alfon

 

I used Mobil 1 0W-20 in my 2004 Prius for most of its life, but I only changed the oil and filter once a year or 10,000 miles. According to used oil analysis, had good results

Why Toyota chose to go with a mandatory synthetic oil change, and keep among the shortest oil change intervals among mass produced vehicles, is a mystery

 

There is all kinds of reasoning for the use of syn oil. 0W-20 is really thin and it seem to me that 0w-30 would be better for Summer heat. But the mandatory thing is something that a lot of us would like the Pruis team to to explain. Any thing else is speculation.

 

5000 miles per oil change on synthetic oil is rather frequent compared to other automobiles using synthetic oil. The main reason for changing oil is because the oil: 1) has broken down and no longer has effective lubricating qualities, and 2) it is contaminated with debris (partially burned hydrocarbons) which cannot be removed by the oil filter. Certainly changing oil frequently isn't going to harm the engine, only your pocket book.

Keith

 

Could you elaborate on the oil and filter change procedure?

 

I don't think anybody has had a 2010 model long enough at this point to document it. The difficulties are the fairing under the motor for improved aerodynamics, that must be opened and its covered in other threads

The filter isn't a spin on, it's a cartridge element. Judging by the complaints - primarily mess - of the cartridge element that is also found on the new Corolla, Tundra, and Sequoia, it's not promising to be as easy a job as it was on my 2004 Prius

 

I would like to know if the dealers are actually using 0W20 oil. I bet they are not.

IMHO Oil change intervals are influenced by many factors. They are not simply dictated by engineering data. The dealers like short intervals since it gives them more chances to upsell. Salesmen like long intervals since they can sell the buyer on the low maintenance requirements. Corporate wants short oil changes since they mask any pontential design defects in the engine, and reduce warranty claims. I believe they have to use the oil specified in the manual during the EPA mileage tests. That is probably why they are telling you to use 0W20.

Oil requirements (viscosity, synthetic/dino) are influenced by many factors too. Note how the manual does not say to use synthetic oil, but you can only get 0W20 in synthetic. In a few years 0W20 will probably be availible in a dino flavor too.

Once your engine is warmed up, there is no difference between a 0W20 and a 5W20. Actually the difference during that short startup time is minimal.

I use synthetic oil in my Gen II and go 10,000 miles between changes. I have done oil analysis, and the oil could last much longer. Everyone has plenty of theories about the importance of changing the engine oil, but dont forget about the transaxle fluid.