5W-20 With Lowest Volitility NOACK Rating?

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ZeeOSix

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It's probably been discussed before, but what full synthetic motor oils have the lowest Volatility NOACK rating in 5W-20? I've found that a lot of manufactures don't always show the NOACK number.

Here's a chart I found for GF-5 rated 5W-30 ... but not sure if it would also apply to 5W-20.

 
I think each oil is different...for example Amsoil's website shows 5.8 NOACK on their 5w20 and 8.5 on their 0w20 - very different than the chart you posted.
 
I would intuit that a 5W20 would have a lower NOACK, all other things being equal, as they don't have to "stretch" it so far.

Looking at the PQIA results for same brands in 5W20 versus 5W30, it looks like a wash...maybe a slight edge to the 5W20, but not really enough to state as a fact.

Citgo Supergard - essentially the same.
http://pqiadata.org/CITGO_Supergard_5W30.html
http://www.pqiadata.org/CITGOSupergard5W20.html

Trop Arctic - essentially the same.
http://www.pqiadata.org/Phillips66TropArtic5W30.html
http://pqiadata.org/Phillips66_Trop_Artic_5W20.html

Assuming that they don't play games (like RP lineup having clearly different basestock blends through the range), I'd be comfortable using that chart that you have for choosing a 5W20.
 
I would use the Red Line in my 1.6 GDI EcoBoost, but fear for the high(er) calcium and ZDDP levels (higher moly content of EITHER type actually has been shown to help stave off LSPI), unless Dave can assure me otherwise.
wink.gif


The Ravenol 5W-30 DXG Dexos 1, Gen 2 formula I plan to use (once Blauparts has it in stock here in the states), has a NOACK right in there with the Red Line on that chart @ 6.0 (maybe because it has a similar base stock PAO/POE blend
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and yeah, I know all about the GTL basestocks in the SOPUS products and how it also has low volatility percentage properties).

It is only a little bit thicker than almost any other 5W-20 I would use (@ a 3.1 HTHSV, Red Line is a 3.0 HTHSV), which is fine for a hard driven, summer OCI turbo GDI setup, and it also uses a trick anti-wear, anti-friction add pack of TRIMER moly and tungsten.
All this for about $2.50 less a liter than Red Line, with a detergent/dispersant pack designed specifically for GDI/turbo setups (I'm guessing that they substitute magnesium/boron/whatever for a high calcium content to get even it's modest 8.3 starting TBN, which is about the same as Red Line's anyway?) and their LSPI problems.
 
Originally Posted By: BrocLuno
Deposits I guess ...


There is fairly strong evidence that a higher NOACK percentage helps accelerate/exacerbate back of intake valve deposit buildup on GDI engines, turbo/boosted GDIs even more so (unless they also have a secondary port injection system in conjunction with the DI, like the current Mustang 5.0 Coyote does).
frown.gif
 
I was trying to find this information for multiple oils, and settled on Valvoline with 7.6% NOACK. I couldn't find test numbers for half the oils I was looking up Also, the 9.3 TBN is pretty good, and it's only $22/5qts.
 
JLTD pretty well got it nailed with the Amsoil SS 5w20 at 5.8. Maybe Red Line might be lower but it may be at the high end as far as thickness goes. Then again I am a little biased towards Amsoil products
 
Originally Posted By: eyeofthetiger
I was trying to find this information for multiple oils, and settled on Valvoline with 7.6% NOACK. I couldn't find test numbers for half the oils I was looking up Also, the 9.3 TBN is pretty good, and it's only $22/5qts.


Is that their 'new formula' "Modern Engine Oil" marketed for T/GDI setups?

Is there an additional Ford oil spec for your engine needed to be compatible with the oil contact timing belt, or is it the same 945-A as they require for my 1.6 which uses a dry timing belt?
 
Originally Posted By: CT8
Why do people worry about the lowest NOACK numbers.


A less volatile oil is less likely to bring ring sticking over time and miles.
This is a real concern with many current engines.
OTOH, I wonder what the NOACK numbers would have been for the various oils I used in various engines over the years with no problems?
 
Does Noack change with age? Say as it gets some wear and tear. Does evaporation go up?

On the flip side, once the lighter compounds initially present in the oil evaporate off, does evaporation slow down?

In short, is Noack a constant?
 
NOACK is measured by a defined test protocol and represents a snapshot of what you'd see with fresh oil.
What you're really asking is how volatility changes with age.
My guess is that it would decline since the most volatile fractions would be evaporated out early in the OCI leaving behind what should be a less volatile blend.
OTOH, fuel dilution might make for greater volatility with use. Fuel dilution is often measured using flash point, which would depend upon volatility.
I'd love to hear from SOJ on this.
 
Originally Posted By: fdcg27
NOACK is measured by a defined test protocol and represents a snapshot of what you'd see with fresh oil.
What you're really asking is how volatility changes with age.
My guess is that it would decline since the most volatile fractions would be evaporated out early in the OCI leaving behind what should be a less volatile blend.
OTOH, fuel dilution might make for greater volatility with use. Fuel dilution is often measured using flash point, which would depend upon volatility.
I'd love to hear from SOJ on this.


That's what I'm thinking, a "high" Noack oil might settle down. Frequent oil changes with that oil would mean worse oil fumes for the PCV system to deal with.

However, in the past I'd swear that oil usage went up as the oil aged. That was 15-20 years ago on cheap conventional, so very likely not relevant here. But if Noack goes up with age, then frequent changes could fight the effects of a high Noack oil. Or that this oil just isn't worth using.
 
You correctly answered your own question.

If you start the engine and run it continuously, non-stop for a month, with a miraculous self-refilling petrol tank, you will strip off the light front end of the oil, the viscosity of the oil will go up, the concentration of DI & VII in the oil will go up and, should you sample the oil and test it, the Noack of the oil in the sump will go down.

On the other hand, if you continually short-trip through the arctic wastes of Southern England, never getting the engine warmed up, and continually condense the unburnt heavy-end of the gasoline into your engine oil, it will thin, additive concentrations will drop and the measured Noack of the oil in the sump will go up.

If you are a normal person, with a normal car, living in a normal temperate country and drive a normal mixed driving cycle, then the Noack of the oil in your sump might bounce around a tiny bit but to all intents and purposes will have the same Noack value as the fresh oil you added at the start of the OCI.
 
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Originally Posted By: SonofJoe
If you are a normal person...


Well, that just ruled out most anyone on BITOG...

Originally Posted By: SonofJoe
You correctly answered your own question.

If you start the engine and run it continuously, non-stop for a month, with a miraculous self-refilling petrol tank, you will strip off the light front end of the oil, the viscosity of the oil will go up, the concentration of DI & VII in the oil will go up and, should you sample the oil and test it, the Noack of the oil in the sump will go down.

On the other hand, if you continually short-trip through the arctic wastes of Southern England, never getting the engine warmed up, and continually condense the unburnt heavy-end of the gasoline into your engine oil, it will thin, additive concentrations will drop and the measured Noack of the oil in the sump will go up.

If you are a normal person, with a normal car, living in a normal temperate country and drive a normal mixed driving cycle, then the Noack of the oil in your sump might bounce around a tiny bit but to all intents and purposes will have the same Noack value as the fresh oil you added at the start of the OCI.


Works for me. That says my wife's car might see high Noack issues, as many of her trips are about 9 miles long. Coolant gets up to temp, but not so sure on oil temp. Probably fine in summer but winter might suffer. Me, most of my trips are 50 miles, so Noack would likely go down with time. So her car might like a low Noack oil, at least in winter, while mine probably wouldn't care--assuming we had cars that Noack was something to worry about (GDI fears). [Thankfully, no worries here.]
 
Originally Posted By: SonofJoe
You correctly answered your own question.

If you start the engine and run it continuously, non-stop for a month, with a miraculous self-refilling petrol tank, you will strip off the light front end of the oil, the viscosity of the oil will go up, the concentration of DI & VII in the oil will go up and, should you sample the oil and test it, the Noack of the oil in the sump will go down.

On the other hand, if you continually short-trip through the arctic wastes of Southern England, never getting the engine warmed up, and continually condense the unburnt heavy-end of the gasoline into your engine oil, it will thin, additive concentrations will drop and the measured Noack of the oil in the sump will go up.

If you are a normal person, with a normal car, living in a normal temperate country and drive a normal mixed driving cycle, then the Noack of the oil in your sump might bounce around a tiny bit but to all intents and purposes will have the same Noack value as the fresh oil you added at the start of the OCI.




Thank you for this informative post.
 
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