I understand the difference in weights of oils and why they make them that way, but what whould happen if you mixed like 1 qt 10w30 with 3 qt 5w30 and 1 qt 0w-30? or other combinations and such. I don't guess it would really be that different from 5 qt of 5w30, but i was just curious about the scientific stand point of this. Obviously different cars require different oils, but lets just say this is a car that can use 5 qt of 5w30 - year round. I want to see what you guys have to say about doing something like this. just been curious about this....
Mixing different weighted oils
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i figured, i'm not speaking about my vehicle specifically, just any vehicle, also wondered if by adding say 2 qts 10w30 to 3 qts 0w-30 would you benefit from both or would cancel each other and meet in the middle? like viscosity break down and shear resistance
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I once mixed VWB 10w40 (3qts) and VWB 20w50 (3QTS) into my dads 80 F-150 I6.
Needless to say, it was summer.. and the truck did NOT like that combination. so it shouldve been 15w45 weight!
The truck ran fine after you gave it some gas to push the oil around, but starting up it struggled.
A week later I put the 10w40 back into it and it was happy.
So I never mix oil weights because of that, (at least not intentionally).
Needless to say, it was summer.. and the truck did NOT like that combination. so it shouldve been 15w45 weight!
The truck ran fine after you gave it some gas to push the oil around, but starting up it struggled.
A week later I put the 10w40 back into it and it was happy.
So I never mix oil weights because of that, (at least not intentionally).
I did a mix of Delo 15w40 and 5w20 Peak Syn for my Honda.
Yes. Mix away.
Yes. Mix away.
IMO....mix away.
I personally do it all of the time. Closeouts at various Kmart store closings, in Fl last summer, enabled me to purchase quite a load of Mobil 1, EP, 5w-20 and later on the clearance of Mobil 1, 15w-50 full synthetic.
I'm now running a blended mix of 4 quarts of M1, EP, 5w-20 and 2 quarts of M1, 15w-50. The oil has 7K miles on it and I'll run it to 10K miles.
Both the M1, EP, 5w-20 and M1, 15w-50 have almost the same viscosity index, per Mobil PDS for both oils.
My 1997 T4Runner, seems to really like this mix through winter and into spring.....I'll change it out hopefully at the end of the summer. Next on deck, for my oil change is Royal Purple, 10w-30, API-SL....compliments of Amazon!
I personally do it all of the time. Closeouts at various Kmart store closings, in Fl last summer, enabled me to purchase quite a load of Mobil 1, EP, 5w-20 and later on the clearance of Mobil 1, 15w-50 full synthetic.
I'm now running a blended mix of 4 quarts of M1, EP, 5w-20 and 2 quarts of M1, 15w-50. The oil has 7K miles on it and I'll run it to 10K miles.
Both the M1, EP, 5w-20 and M1, 15w-50 have almost the same viscosity index, per Mobil PDS for both oils.
My 1997 T4Runner, seems to really like this mix through winter and into spring.....I'll change it out hopefully at the end of the summer. Next on deck, for my oil change is Royal Purple, 10w-30, API-SL....compliments of Amazon!
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First you need to look up the underlying viscosity spec's for each specific oil which can be found from the oil companies Product Data Sheets (PDS).
Then you can plug the values into a viscosity blending calculator such as the following:
http://www.widman.biz/English/Calculators/Mixtures.html
If you're still with me, then you're ready to learn that it is really the HTHSV and VI that matters most and whether an oil is a 0W-30 5W-30 or 10W-30 has little meaning or value in a Mississippi climate.
Then you can plug the values into a viscosity blending calculator such as the following:
http://www.widman.biz/English/Calculators/Mixtures.html
If you're still with me, then you're ready to learn that it is really the HTHSV and VI that matters most and whether an oil is a 0W-30 5W-30 or 10W-30 has little meaning or value in a Mississippi climate.
Originally Posted By: widman
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
It's not ever recommended. It's ok to mix oils being most use similar chemistry, but it's not ideal and never is.
When's the last time you heard a formulator say "Yeah man, blend some of that RLI with the RL to get your VI up to 230 and then add some Royal Purple in there to get more of that Synerlec. That will go well with that RL Moly."
When's the last time you heard a formulator say "Yeah man, blend some of that RLI with the RL to get your VI up to 230 and then add some Royal Purple in there to get more of that Synerlec. That will go well with that RL Moly."
Not every grade of a particular brand of engine oil shares an identical additive formulation. This is very obvious in the WPP/WNE oils. In other brands, even though major detergent/dispersant numbers look the same on paper, base oils can differ by grade, along with unreported additives.
Originally Posted By: CATERHAM
Simply changing brands means you'll be running a mix for the first oil change at least.
I hate doing even that, so you're on your own in this battle.
Simply changing brands means you'll be running a mix for the first oil change at least.
I hate doing even that, so you're on your own in this battle.
Mix away.
Originally Posted By: CATERHAM
Originally Posted By: widman
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
Assuming a proper drain, I can't see how maybe a ½ pint of used oil is going to have much, if any effect on the fresh fill... Again assuming the oil was used long enough to deplete most of the additive package, there isn't going to be much difference than if the same oil were used again...
No unless I'm doing a flush on a old beater engine(usually less than 200-300 miles), I won't mix different brands but have no issue using different weights of similar oils within a brand... Just did a OC of approx 60/40 M1 0W-40 & 5W-20EP...
Originally Posted By: widman
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
Assuming a proper drain, I can't see how maybe a ½ pint of used oil is going to have much, if any effect on the fresh fill... Again assuming the oil was used long enough to deplete most of the additive package, there isn't going to be much difference than if the same oil were used again...
No unless I'm doing a flush on a old beater engine(usually less than 200-300 miles), I won't mix different brands but have no issue using different weights of similar oils within a brand... Just did a OC of approx 60/40 M1 0W-40 & 5W-20EP...
Originally Posted By: TFB1
Originally Posted By: CATERHAM
Originally Posted By: widman
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
Assuming a proper drain, I can't see how maybe a ½ pint of used oil is going to have much, if any effect on the fresh fill... Again assuming the oil was used long enough to deplete most of the additive package, there isn't going to be much difference than if the same oil were used again...
No unless I'm doing a flush on a old beater engine(usually less than 200-300 miles), I won't mix different brands but have no issue using different weights of similar oils within a brand... Just did a OC of approx 60/40 M1 0W-40 & 5W-20EP...
I had mixed different brands and different brand weights in my 97 F150.
Originally Posted By: CATERHAM
Originally Posted By: widman
It is not recommended to mix brands/formulations.
.
Except it's recommended all the time by EVERY formulator our there.
Simply changing brands means you'll be running a mix for the first oil change at least.
IMO the whole question is much ado about nothing.
Assuming a proper drain, I can't see how maybe a ½ pint of used oil is going to have much, if any effect on the fresh fill... Again assuming the oil was used long enough to deplete most of the additive package, there isn't going to be much difference than if the same oil were used again...
No unless I'm doing a flush on a old beater engine(usually less than 200-300 miles), I won't mix different brands but have no issue using different weights of similar oils within a brand... Just did a OC of approx 60/40 M1 0W-40 & 5W-20EP...
I had mixed different brands and different brand weights in my 97 F150.
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