0w-30 vs. 5w-30

[JohnnyO]

Still kinda new here, so forgive if this is a stupid question. My '02 Ranger and wife's '99 Grand Am both call for 5w-30 and I've run that in Mobil 1 for a while. M1 has a 0w-30 "enhanced fuel economy formula" or some such, would that be okay, especially in the winter? Thanks.

 

[icruse]

The Mobil 1 0W30 would work fine in place of the Mobil 1 5W30; I have used both in my 93 Grand Prix.
The 0W30 does give you better fuel mileage. And it actually is okay to use all year round.
Another thing is that the 0W30 is formulated just a tad bit thicker than the 5W30.

Good Day,
Steven

 

[Roger]

Everyone talks about the advantage of 0W30 in cold temperatures. But what about when it's hot?

Mobil 1's 0W30 lists a 10.3 viscosity at 100 C while M1 5W30 comes in at 10.0. Shouldn't the 0W30 provide better warm temperature performance as well?

 

[jsharp]

My experience with M1 0W-30 was not good. I tried it in a vehicle that had used M1 5W-30 since breakin. With the 0W-30 it started consuming a quart in about 5000 miles where with the 5W-30 it had used none over the same mileage interval. I went back to 5W-30, the oil consumption returned to normal (none), and I never bothered to try it again. IMO, unless you're in an extremely cold climate I don't see how 0W-30 would offer any advantages, and even then only in the coldest months...

 

[rpn453]

quote:

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Originally posted by Roger:
Everyone talks about the advantage of 0W30 in cold temperatures. But what about when it's hot?

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Unless the base stock is better for the 0W-30 than the 5W-30 or 10W-30, then the oils with the lower spreads will perform better in hot weather due to less VI improvers. But M1 0W-30 has a higher flash point than M1 5W-30 (suggesting a higher quality base stock - more high temperature stability), so I don't know why jsharp had consumption problems.

Maybe it was an older formulation?

 

[TooSlick]

rpn453,

Flashpoints really aren't that relevant to oil consumption. What you will find is that the 0w-30 and 0w-40 grades normally have a higher Noack volatility than the 5w-30 and 10w-30 grades. The Noack test tells you how much oil evaporates under controlled conditions and is a much better predictor of oil consumption.

TS

 

[jsharp]

quote:

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Originally posted by rpn453:

quote:

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Originally posted by Roger:
Everyone talks about the advantage of 0W30 in cold temperatures. But what about when it's hot?

---

Unless the base stock is better for the 0W-30 than the 5W-30 or 10W-30, then the oils with the lower spreads will perform better in hot weather due to less VI improvers. But M1 0W-30 has a higher flash point than M1 5W-30 (suggesting a higher quality base stock - more high temperature stability), so I don't know why jsharp had consumption problems.

Maybe it was an older formulation?

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Yes, it was one of the early formulations of 0W-30. Since then I've beed satisfied with 5W-30 so I've never bothered to try it again...

 

[rpn453]

quote:

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Originally posted by TooSlick:
Flashpoints really aren't that relevant to oil consumption. What you will find is that the 0w-30 and 0w-40 grades normally have a higher Noack volatility than the 5w-30 and 10w-30 grades. The Noack test tells you how much oil evaporates under controlled conditions and is a much better predictor of oil consumption.
TS

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I guess Noack would be a better indicator. I didn’t think of that immediately because that test is not included on data sheets as often as I’d like to see. But I think flashpoint still has relevancy: a higher flashpoint usually corresponds with a lower Noack value. They are both based on volatility.