What type / brand of factory oil ... and

I have been changing my oil in my 2003 Jetta TDI (Turbo Diesel w/ 5-speed manual tanny) every 10,000 miles for over 130,000 miles with Mobil Delvac 5 W 40 (full synthetic) with no problems and negligible oil usage.

Our Prius, after the initial 5,000 mile change it has been every 10,000 miles with 0W20 Mobil One (full synthetic) and once with Valvoline 0x20 full synthetic oil, I and only put in 4 quarts so not to overfill. The Prius has over 33,000 miles and negligible oil usage.

alfon

 

I did first oil change at 3500 miles and I am getting about 3 MPG be-tor.....Valvoline 0W20 synthetic oil...:rockon:

 

Over at bobistheoilguy.com, there is good evidence to suggest that the older 0W-20 oil supplied here in the USA and sold in Toyota branded oi bottles was made by Nippon oil, which also makes the Eneos brand. This does not mean that the Eneos 0W-20 is identical to the original Toyota 0W-20, but the specs of the Eneos oil seem like it is a close match. I would use it without hesitation.

The current production of the Toyota branded 0W-20 oil has been switched to ExxonMobil. At least one reason given for the switch, again posted over at bobistheoilguy.com, is that Nippon oil had issues supplying the quantities of bulk 0W-20 needed by dealers. I would suspect that other issues were involved as well (price, availability, etc.).

Again, this definitely does not mean that the new Toyota 0W-20 is the same as Mobil 1 0W-20, quite the contrary. Virgin oil analysis shows that the ExxonMobil Source Toyota 0W-20 is very similar to the Nippon oil sourced 0W-20 and very different from the properties of Mobil 1 0W-20. The differences are primarily in the much larger amount of Molybdenum in the Toyota oil (almost 10X the amount in Mobil 1 0W-20) and the much higher viscosity index of the Toyota 0W-20 oil, which gives better cold start properties for most climates. Viscosity index is a measure of how much the viscosity of a liquid changes with temperature. The higher the index the less the viscosity changes.

Rumple

 

For my 20,000 change, I brought in Eneos brand oil I purchase from Amazon to my dealer. They were happy to put it in for me, and for the 6,000 miles since, I can clearly see a 2-3 MPG increase over what I used to get last year. I'm very happy with the results.

 

That's right, let's put in some motor oil and pick up 2mpg. If everyone can do that, there will never be gas guzzlers

 

The raises the question as to why Toyota would add all that moly?

Is there some high pressure sliding contact in a Prius engine that others don't have?

 

Good question. Honda brand 0W-20 motor oil also shows the same unusual properties as Toyota brand 0W-20 - extremely high moly coupled with a high viscosity index. The question is why do both Toyota and Honda feel that these properties are important for their engines?

While these questions are interesting, I do think that, as it states in the owners manual, any API SM/ ILSAC-GL-4 0W-20 will work well in the 1.8L engine in the Prius.

That being said, I have chosen to use Toyota brand 0W-20 oil in my Prius just in case there is some important wear or cold start issue that will be better controlled by using an oil with the properties that Toyota (and Honda!) think important.

A new, unusual 0W-20 has come out - Castrol Edge 0W-20. This oil has an even higher viscosity index than the Toyota or Honda 0W-20 oils, but has very little moly. Instead it has titanium which is part of a very unusual antiwear additive(possibly titanium diboride?). Certainly an oil that should be high on the list of oils to use in a Prius.

Here are several 0W-20 oils compared. The black bottle Toyota is the newer ExxonMobil sourced oil and the red bottle is the older Nippon oil based stock.

Rumple

 

I did an early oil change, 1500 miles, because I believe it's good to get the stuff from the manufacturing process out fairly early. If I am wrong at least no harm has been done, less than $40 for a DIY oil change. Have been using Mobil 1 0W20 since that change. I am on my second 10K interval and will have a UOA done when I change it at 30K miles next month.

 

Oil with new car purchase was full synthetic from manufacturer. Brought in for 10,000 change (toyota dealer) and they put regular (5,000 mi oil change type.) I am concerned about the switch back and forth and why they would opt to do it this way to begin with. I mean the oil interacts with everything and I was "taught" to stay with the same fuel and consistency (unless in the "old days" we would change it for weather adjustment) CAN I REQUIRE TOYOTA TO USE FULLY SYNTHETIC TO MATCH THE MANUFACTURERS SPECS ON ARRIVAL?

 

The Toyota dealers are independently owned businesses and have great leeway in what they do in their repair departments.

You can refuse to go to a dealer who does not put in the recommended synthetic 0W-20 oil. An oil change is a simple procedure, you could find a reputable shop and go there for oil changes. Many will do an oil change with the oil and filter that you supply - charging only for the labor. This way your are sure what oil went into your car.

But "require" a dealer to use any particular oil and have them comply against their will? No. Vote with your feet, as the saying goes.

Rumple

 

Be careful, some dealers have been known to put in Penzoil 10W40 out of their oil durm and charge the unaware Prius owner for Toyota 0W20. If I had to use a dealer to change my oil (instead of doing it myself) I would not trust them unless I could watch them put the oil in. As Rumpledoll says you can take your own oil, but if you do make sure you get back the remainder of the 5th quart. The car should take about 4.2 or 4.3 quarts which will leave it about 1//4 inch below the full mark. Also check the oil level yourself when you get the car back.

Remember the Service Manager or the Prius Technician is not going to be changing your oil, they will most likely have a kid making minimum wage doing that kind of work. He may have been flipping burgers at Micky Ds the week before.

 

i was under the impression that all oil at 0w20 was synthetic.

 

It's rather confusing, there are Group III, IV, and V synthetics. There are true synthetics and synthetic blends and other marketing names as well.

[ame="http://en.wikipedia.org/wiki/Motor_oil"]Motor oil - Wikipedia, the free encyclopedia[/ame]


I think the ones we are using, i.e. Mobil 1, Toyota, Enos, Amsoil, Valvoline, and some others are synthetics. I'm not sure about Honda's 0W20 it may not be. I understand there is nothing that prevents making a 0WXX oil that is not a synthetic, but at this time most of them are.