5W-30 vs 0W-30 Does it matter?

[PurdueRy]

I was doing some reading tonight about different oil types since I have to change my oil soon in my 2007 G6 GT coupe.

I read that Mobil came out with a "high economy" 0W-30 oil which supposedly COULD give you a 2% increase in fuel economy. I realize that's hardly anything...but seeing as it doesn't cost me anything...

Now, I am naturally skeptical. But it did get me interested. I live in Michigan...but we're coming out of winter now(although we did just get snow yesterday ) Would it be ok to try out 0W-30 to see if I notice any difference in economy?

and yes, manual recommends 5W-30.

Thanks everyone.

EDIT: Oh and Linky

EDIT2: Is there any good place to buy air/oil filters and oil online?

 

[fstime]

You're not going to et 5-10% of an increase.

Stay with 5w-30 unless you live on the south pole.

Would it hurt? Probably not. Both oils are the same thickness at operating temps.

 

[PurdueRy]

Originally posted by: BouZouki
You're not going to et 5-10% of an increase.

Stay with 5w-30 unless you live on the south pole.

Would it hurt? Probably not. Both oils are the same thickness at operating temps.

The numbers must have gotten screwed up in my head I meant 2%.

 

[PurdueRy]

Let me ask this....will using 0w-30 in a car be worse in any way than using 5W-30. I figure if not I will give it a try...its the same price.

From what I read I would say no it won't matter but I am looking for confirmation.

 

[desy]

In Michigan no
In Texas maybe

 

[PurdueRy]

Originally posted by: desy
In Michigan no
In Texas maybe

Why is that? If I lived in a warm area wouldn't any 30 weight oil be closer to 30? The only case where I can see it mattering is when its really REALLY cold. Otherwise aren't they the same?

 

[desy]

It has more to do with start-up and the degradation of the oil



The downside of a mineral based multigrade oil is that this VI additive wears out over time and you end up with the original straight 10 weight oil. It will go back to being too thin when hot. It will have a thickness of 6 instead of 10. This may be why Porsche (according to some people) does not want a 0W-30 but rather a 10W-30. If the VI wears out the 0W-30 will ultimately be thinner, a straight 0 weight oil. When the VI is used up in the 10W-30 oil it too is thinner. It goes back to a straight 10 weight oil. They are both still too thick at startup, both of them. The straight 0 weight oil, a 5 weight oil and a 10 weight oil are all too thick at startup.

This is just theory however. With normal oil change intervals the VI improver will not wear out and so the problem does not really exist. In fact, oils do thin a little with use. This is partly from dilution with blow by gasoline and partly from VI improvers being used up. What is more interesting is that with further use motor oils actually thicken and this is much worse than the minimal thinning that may have occurred earlier.

Synthetic oils are a whole different story. There is no VI improver added so there is nothing to wear out. The actual oil molecules never wear out. You could almost use the same oil forever. The problem is that there are other additives and they do get used up. I suppose if there was a good way to keep oil clean you could just add a can of additives every 6 months and just change the filter, never changing the oil.

http://www.toyotatundraforum.c...7-motor-oil-101-a.html

 

[PurdueRy]

Originally posted by: desy
It has more to do with start-up and the degradation of the oil



The downside of a mineral based multigrade oil is that this VI additive wears out over time and you end up with the original straight 10 weight oil. It will go back to being too thin when hot. It will have a thickness of 6 instead of 10. This may be why Porsche (according to some people) does not want a 0W-30 but rather a 10W-30. If the VI wears out the 0W-30 will ultimately be thinner, a straight 0 weight oil. When the VI is used up in the 10W-30 oil it too is thinner. It goes back to a straight 10 weight oil. They are both still too thick at startup, both of them. The straight 0 weight oil, a 5 weight oil and a 10 weight oil are all too thick at startup.

This is just theory however. With normal oil change intervals the VI improver will not wear out and so the problem does not really exist. In fact, oils do thin a little with use. This is partly from dilution with blow by gasoline and partly from VI improvers being used up. What is more interesting is that with further use motor oils actually thicken and this is much worse than the minimal thinning that may have occurred earlier.

Synthetic oils are a whole different story. There is no VI improver added so there is nothing to wear out. The actual oil molecules never wear out. You could almost use the same oil forever. The problem is that there are other additives and they do get used up. I suppose if there was a good way to keep oil clean you could just add a can of additives every 6 months and just change the filter, never changing the oil.

http://www.toyotatundraforum.c...7-motor-oil-101-a.html

Thanks for the detailed info. Since this is synthetic it looks like theirs no harm in giving it a try.

Thanks again!