Can someone explain to me what the major difference is between the two? If I understand correctly the 0w30 is thinner at startup. Is this right? Also if a vehicle specs 5w30 is there any benefit (or detriment) to using a 0w30?
5w30 vs 0w30
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Both will be -ABOUT- the same viscosity when at operating temperatures, but as the temperature of the oil drops, the 5w30 will generally thicken more than the 0w30 will. The difference generally gets more dramatic as temperatures fall toward freezing and below.
In my opinion, there is absolutely no detriment to using a 0w30 where a 5w30 is specified, and in fact, I'm becoming of the opinion that 0W- oils are beneficial to everyone, including those who live in hot climates. Even a 100*F cold start is "cold" for motor oil, and the 0w30 will generally flow faster than a 5w30 will...even at 100*F.
I use the word "generally" a lot. That is because these numbers are viscosity grades, with allowable ranges associated with them. So sometimes you can have an oil that's on the "thick" end of a range and an oil that's on the "thin" end of a range and still have the same grade printed on the bottle. It's totally possible that the 0w30 might be thicker than the 5w30 at operating temperature...but both would still be in the range allowed to be labeled "30".
In my opinion, there is absolutely no detriment to using a 0w30 where a 5w30 is specified, and in fact, I'm becoming of the opinion that 0W- oils are beneficial to everyone, including those who live in hot climates. Even a 100*F cold start is "cold" for motor oil, and the 0w30 will generally flow faster than a 5w30 will...even at 100*F.
I use the word "generally" a lot. That is because these numbers are viscosity grades, with allowable ranges associated with them. So sometimes you can have an oil that's on the "thick" end of a range and an oil that's on the "thin" end of a range and still have the same grade printed on the bottle. It's totally possible that the 0w30 might be thicker than the 5w30 at operating temperature...but both would still be in the range allowed to be labeled "30".
0w-30 is not thinner at start up. Some 0w30 are actually thicker than 5w30 oils, the difference is the pumpabililty and being able to flow easier in cold/ambient temperatures. In very cold weather there is an advantage to using a 0w30 as the oil flows easier, however in warmer climates there is not as much of an advantage.
Originally Posted By: fisher83
Can someone explain to me what the major difference is between the two? If I understand correctly the 0w30 is thinner at startup. Is this right?
Basically, yes. Or more correctly, the 0w30 is not as thick as 5w30 at very low (sub-freezing) start-up temps. But you'd need to look at spec sheets of the specific oils you're considering and see MRV and CCV numbers to determine the actual cold flow properties. Sometimes the devil is in the details and some 0w30 oils aren't very different from 5w30 oils until you reach temps way way below freezing.
Can someone explain to me what the major difference is between the two? If I understand correctly the 0w30 is thinner at startup. Is this right?
Basically, yes. Or more correctly, the 0w30 is not as thick as 5w30 at very low (sub-freezing) start-up temps. But you'd need to look at spec sheets of the specific oils you're considering and see MRV and CCV numbers to determine the actual cold flow properties. Sometimes the devil is in the details and some 0w30 oils aren't very different from 5w30 oils until you reach temps way way below freezing.
Different pumpability specs at extremely cold temps. I think the 5w30 spec is less than 6600cP at -30C whereas the 0w30 spec is less than 6600cP at -35C
From a spec standpoint, Mobil 1 5w30 is 11.0cSt vs 0w30 at 10.9 cSt @100C
5w30 is actually thinner @40C, 61.7cSt vs 62.9cSt for 0w30
Pour point however is -42 for the Mobil 1 5w30 and -50 for the 0w30.
Mobil 1 does give an MRV specification for the 0w30 but not the 5w30.
So when you talk about one oil being thinner at startup, I think you'll have to specify what temp you are talking about. In the case of Mobil 1, on a hot summer day the 0w30 may actually be thicker at startup. At operating temperature, the 5w30 and 0w30 are just about identical. If you live in Alaska, the Yukon or Siberia, the 0w30 is probably better.
From a spec standpoint, Mobil 1 5w30 is 11.0cSt vs 0w30 at 10.9 cSt @100C
5w30 is actually thinner @40C, 61.7cSt vs 62.9cSt for 0w30
Pour point however is -42 for the Mobil 1 5w30 and -50 for the 0w30.
Mobil 1 does give an MRV specification for the 0w30 but not the 5w30.
So when you talk about one oil being thinner at startup, I think you'll have to specify what temp you are talking about. In the case of Mobil 1, on a hot summer day the 0w30 may actually be thicker at startup. At operating temperature, the 5w30 and 0w30 are just about identical. If you live in Alaska, the Yukon or Siberia, the 0w30 is probably better.
Thanks for all the quick replies! It is just something I was curious about. I'll probably just stick with 5w30 but I just wondered if I would gain anything besides maybe 0.0000001 mpg by using a 0w30 instead. I live in Nebraska so it does occasionally get below zero in the winter but not that often. This year was actually unseasonably warm. We are around 80 degrees the past week or two which is nearly 20 degrees above average for this area. We don't really see too many temperature extremes around here so it sounds like the 0w30 would not likely provide me any noticeable benefit. Thanks again!
Originally Posted By: fisher83
I just wondered if I would gain anything besides maybe 0.0000001 mpg by using a 0w30 instead.
You're not going to achieve any MPG benefit because when at operating temp, both grades will perform about the same. You'd have to go down to Xw-20 grade for some MPG improvement.
The main benefit of 0w-XX grade is lower cold start-up wear. But as was explained earlier, you'd really need to be in Siberia or Alaska somewhere in the dead of winter for the differences in cold flow to become apparent.
I just wondered if I would gain anything besides maybe 0.0000001 mpg by using a 0w30 instead.
You're not going to achieve any MPG benefit because when at operating temp, both grades will perform about the same. You'd have to go down to Xw-20 grade for some MPG improvement.
The main benefit of 0w-XX grade is lower cold start-up wear. But as was explained earlier, you'd really need to be in Siberia or Alaska somewhere in the dead of winter for the differences in cold flow to become apparent.
Originally Posted By: Quattro Pete
Originally Posted By: fisher83
I just wondered if I would gain anything besides maybe 0.0000001 mpg by using a 0w30 instead.
You're not going to achieve any MPG benefit because when at operating temp, both grades will perform about the same. You'd have to go down to Xw-20 grade for some MPG improvement.
The main benefit of 0w-XX grade is lower cold start-up wear. But as was explained earlier, you'd really need to be in Siberia or Alaska somewhere in the dead of winter for the differences in cold flow to become apparent.
That may or may not be true. MPG is tied to HTHS more than anything else. In the case of Mobil 1 the 0w30 has a lower HTHS than 5w30 to improve fuel economy. Perhaps with GC that isn't the case.
But also having a lower viscosity from startup to full temperature would improve fuel economy, but like you said this depends on the assumption that the 0w30 in question is thinner which it may not be. But if all we're talking is the two Mobil 1 oils than it is.
Originally Posted By: fisher83
I just wondered if I would gain anything besides maybe 0.0000001 mpg by using a 0w30 instead.
You're not going to achieve any MPG benefit because when at operating temp, both grades will perform about the same. You'd have to go down to Xw-20 grade for some MPG improvement.
The main benefit of 0w-XX grade is lower cold start-up wear. But as was explained earlier, you'd really need to be in Siberia or Alaska somewhere in the dead of winter for the differences in cold flow to become apparent.
That may or may not be true. MPG is tied to HTHS more than anything else. In the case of Mobil 1 the 0w30 has a lower HTHS than 5w30 to improve fuel economy. Perhaps with GC that isn't the case.
But also having a lower viscosity from startup to full temperature would improve fuel economy, but like you said this depends on the assumption that the 0w30 in question is thinner which it may not be. But if all we're talking is the two Mobil 1 oils than it is.
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The only readily available light 0w30 in the States is Mobil 1 Advanced Fuel Economy.
And yes IMO it would be worthwhile to use this oil in a Nabraska winter over any 5w30.
And yes IMO it would be worthwhile to use this oil in a Nabraska winter over any 5w30.
0W-30 usually has more Noack then 5w30 motor oil.
We had sub zero temperatures this past winter and last winter, and it typically doesn't get that cold in SE michigan, though it usually does get cold in the winter (but rarely drops below 0 degrees F as it did many times this winter), so this winter, 0w30 obviously helped and I used Mobil 1 0w30 for my fill and it currently in the car. I changed it out on new years day (we had a warm december) and I had 5w30 before, and I plan to change the oil again. It can still get cold, or 20/30s overnight and I park my car outside, so would 0w30 help with cold starts now (highs in the 50s 60s now) or would I be fine with 5w30 now, given these temperatures? What's the range or cutoff for when 5w30 is recommended (i'll definitely use that over the summer) and will it act the same at semi-cold temperatures such as 20-40 degrees fahrenheit overnight? Thanks.
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There is no "cut off", you can continue to use the 0w-30.
as stated pumpability comes into play as does the oil group rating, generally real synthetic group IV + V oils do better in the cold. group III legally synthetic processed crude oil flows better but undisclosed amounts of Group IV or V base oils are prolly needed to meet the 0-w rating. generally 0-w oils higher not better Noack is common. looking at the Amsoil site you can compare specs easily, i see the noack for the 0w-40 is a touch better than their 0w-30, pablo commented on the smell of ester oil, some ester oil is used in amsoil's signature series but the 0w-40 may have more. Amsoil gives more specs than anyone i know but they don't tell you exactly what is blended into each product. my choice for Pa weather is 10-30 year around, great low noack + very good pumpability with a better film strength as well. 0w30 is readily available by phone call or pick-up if your close to a warehouse. i can't understand peoples comment's hard to get!!!! feel free to correct any misinformation as i am always looking to learn
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A 0-XX has better pumpability than a 5-XX at very cold temperatures.
That's basically it, and the 0W or 5W qualifications are based upon tests intended to measure pumpability.
There are 0W-30s that have high enough HTHSV to meet various Euro certs, like GC and there are others that don't even come close, like Mobil 1 Advanced Fuel Economy.
The main benefit would be in potentially easier starts in well below 0F ambient temperatures.
There probably isn't any downside.
If you check the Mobil 1 site, you'll find that XOM recommends their 0W-XX oils for most 5W-XX applicatons.
For the same bucks, I'd run AFE over Mobil 1 5W-XX.
JMHO
That's basically it, and the 0W or 5W qualifications are based upon tests intended to measure pumpability.
There are 0W-30s that have high enough HTHSV to meet various Euro certs, like GC and there are others that don't even come close, like Mobil 1 Advanced Fuel Economy.
The main benefit would be in potentially easier starts in well below 0F ambient temperatures.
There probably isn't any downside.
If you check the Mobil 1 site, you'll find that XOM recommends their 0W-XX oils for most 5W-XX applicatons.
For the same bucks, I'd run AFE over Mobil 1 5W-XX.
JMHO
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