Simple mixing question

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2014 sienna takes 6.4 quarts of 0w20. I have a 5 qt jug of 0w20 (PP) and a partial jug of 5W30(PP).

If I put 5qt of 0w20 and and 1.4QT of 5W30 PP what would the equivalent viscosity be? Something in the 5w20 range?
 
I don't know what the viscosity would be but I think it would be fine for use in Texas....especially since they are from the same oil family (similar additive package)....
 
I guessed it wouldn't be, and it isn't.

It can't be calculated, but will be skewed toward the lower viscosity component.
 
PP 5W30 is 10.3cSt
PP 0W20 is 8.3cSt
~78% 0W20
Mix is 8.7cSt, or in 20 grade range.
The W rating is harder to calculate becuase they are done at different temperatures.. IT may or may not fail a 0W test run in a lab. My gut instinct is that it would be super border on 0W/5W

Ref:
http://www.pennzoil.com/en_us/products/f...c-Motor-Oil.pdf
http://www.pennzoil.com/en_us/products/f...c-Motor-Oil.pdf
http://www.widman.biz/English/Tables/J300.html
http://www.widman.biz/English/Calculators/Mixtures.html
 
You can Google "Widman Calculator" to determine the viscosity of a blend of two oils. You'll have to know the product specs to do this, but you can find them on Pennzoil's website.

But, as Pennzoil motor oils tend to be on the light side of a viscosity range, the mixture you're talking about will almost surely be in the 20- weight grade at 100C. Keep in mind that a viscosity specification allows a range of viscosities to qualify. For example, a 20-weight oil at 100C can have a viscosity of between 6.9 and 9.2 cenistokes (cSt), but most oils are in the 8.0-9.0 range. I'd guess your proposed mixture would wind up at around 8.6, or about like a typical 20-weight.
 
Originally Posted By: Ducked

It can't be calculated, but will be skewed toward the lower viscosity component.


Shannow posted something a couple months ago.

Apparently, it gets skewed to the high viscosity components.
 
Originally Posted By: Colt45ws

The W rating is harder to calculate becuase they are done at different temperatures.


He's in Texas.... Effectively, he can ignore the W numbers. Even on those cold snap days up in the panhandle that happen a few days each winter.
 
Originally Posted By: Colt45ws
PP 5W30 is 10.3cSt
PP 0W20 is 8.3cSt
~78% 0W20
Mix is 8.7cSt, or in 20 grade range.
The W rating is harder to calculate becuase they are done at different temperatures.. IT may or may not fail a 0W test run in a lab. My gut instinct is that it would be super border on 0W/5W

Ref:
http://www.pennzoil.com/en_us/products/f...c-Motor-Oil.pdf
http://www.pennzoil.com/en_us/products/f...c-Motor-Oil.pdf
http://www.widman.biz/English/Tables/J300.html
http://www.widman.biz/English/Calculators/Mixtures.html


Sorry, I shouldn't have said it can't be calculated, but its my understanding that for multigrades it can't be calculated with much confidence in the accuracy of the result.
 
Oil is cheap, engines aren't. I don't think 1 or 2 quarts of full synthetic is going to sway anyone's finances one way or another, but a damaged engine might.

I used to mix oils all the time. But now with modern engines, I don't think it's worth the risk.
 
Originally Posted By: Linctex
Originally Posted By: Ducked

It can't be calculated, but will be skewed toward the lower viscosity component.


Shannow posted something a couple months ago.

Apparently, it gets skewed to the high viscosity components.


That's the sort of thing I could get the wrong way around, but I doubt Molakule would be agreeing with me if I did.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/4279826/Ducked#Post4279826
 
Approximately 1.09w22.18.
grin.gif


Just run it.
 
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While there is no way of really knowing, my guess is that you'll end up with an oil that'll be of the 5W-20 grade.
Many of us were adamantly opposed to mixing until Sonofjoe posted a reply in another thread that put most of our concerns to rest.
Nothing weird will happen with this mix and it seems convenient for you.
It's not as though a 0W qualified oil is needed in Texas or just about anywhere else in the lower forty eight.
 
Jury is still out from me, as I've received PMs from another blender in the industry, along with the reply from Pennzoil.

I still think mixing two disparate 0Ws is risky if you need 0W, am confident that the KV100 calced will be pretty close. The non linear aspects of AW additives may well be synergistic...maybe the Sasha Gray blend IS the best of all.

Have always maintained that catastrophy is unlikely (unless you really need that 0W, but everything survived on 10W for ages)

It'll likely be a 5W20, maybe at the thickish end.
 
Originally Posted By: Shannow
Jury is still out from me, as I've received PMs from another blender in the industry, along with the reply from Pennzoil.

I still think mixing two disparate 0Ws is risky if you need 0W, am confident that the KV100 calced will be pretty close. The non linear aspects of AW additives may well be synergistic...maybe the Sasha Gray blend IS the best of all.

Have always maintained that catastrophy is unlikely (unless you really need that 0W, but everything survived on 10W for ages)

It'll likely be a 5W20, maybe at the thickish end.


Aptly echoes my position on the matter as well.
thumbsup2.gif
 
Well, Sonofjoe might disagree WRT the W qualification met when mixing two oils of the same W qual, but in this case it doesn't matter and the oils are of dissimilar W numbers anyway.
The OP lives in a place where below freezing temperatures are mild and of short duration.
He doesn't even need a 5W qualified oil, much less a 0W.
Also, he's mixing two oils of totally similar add packs, so there's no concern with how they'll play together.
The OP proposes a mix I'd be comfortable with even here.
Glad we agree on the likely grade, though!
 
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