Mixing Motul 300V 5W30 and 15W50

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Nov 22, 2020
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Good morning folks. I am under the impression that since both oils are ester core, that they may be mixed without issue to attain the viscosity closer to my needs. Any thoughts on this would be greatly appreciated.
 
At the moment, there is really no need. I just have the two flavors and less of a need, per say of a heavy 50wt. So, in the future, I would like to thin the 50wt out a bit (for whatever the need may be in the future). Completely hypothetical on my end.
 
Any oil that is API licensed (or independently passes ASTM D6922) must be miscible with any other oil that passes the same test. But, that only means the mixture will not cause harm and doesn't mean it will still meet any license, specification nor approval that each individual oil may carry. It has a lot more to do with the additive packages rather than the base oil composition.

Here is the Widman calculator:

 
Thank you sir. Just was wondering if any of the folks in the know would have a better idea of the additive package(s) in the 300V. I am under the impression from my initial research, that the 300V line has no issues in regards to this. Just hoping that the two are not wildly in opposition to each other with regards to additives and the like. Thank you for your response.
 
There is. However, I have a stash of six liters of the 5W30 and 12 liters of the 15W50 that I was able to procure for free. I have no idea what it will go in in the future.
 
is it their racing oil or a street oil?

PS if anyone wants some motul 5w30 power racing in 2liter metal cans cheap.. let me know.
I have about 15 left. (30 liters)
 
Any oil that is API licensed (or independently passes ASTM D6922) must be miscible with any other oil that passes the same test. But, that only means the mixture will not cause harm and doesn't mean it will still meet any license, specification nor approval that each individual oil may carry. It has a lot more to do with the additive packages rather than the base oil composition.

Here is the Widman calculator:

300V is not API licensed and Motul actually says not to mix with other oils. I am not sure whether that applies to another 300V.
 
Thank you sir. Just was wondering if any of the folks in the know would have a better idea of the additive package(s) in the 300V. I am under the impression from my initial research, that the 300V line has no issues in regards to this. Just hoping that the two are not wildly in opposition to each other with regards to additives and the like. Thank you for your response.
300V is not long OCI oil. TBN is somewhere around 7 to 8. It is Ester which means a lot of starting TAN.
IMO, they can be mixed. I would if I had two on the shelf. But, not running too long.
 
Thank you guys for the input. I am under the impression that two 300V ester core oils can be mixed. However, I just wanted to solicit some responses from any of the tribologists who may think otherwise due to the (hypothetically) vastly different additives between the 5W30 and 15W50. Maybe the additives are the exact same...
 
300V is not API licensed and Motul actually says not to mix with other oils. I am not sure whether that applies to another 300V.
Yes, the risk you take with unlicensed and uncertified oils. People like to think they are "better" for a variety of reasons, most of which have no basis in fact (just a strong desire to believe).
 
Yes, the risk you take with unlicensed and uncertified oils. People like to think they are "better" for a variety of reasons, most of which have no basis in fact (just a strong desire to believe).
Motul is actually very specific about this oil and its intended purpose. It is racing oil. It works phenomenally on track.
 
Really dude?
there are 2 versions the black plastic bottle and the metal container.

since this is all hypothetical and you wont even give an application I am sure mixing the 2 and burning it in the oil burning furnace would work fine.

If for example it was to be used in a 2020 toyota tundra.. well those spec 0w20? so I wouldnt recommend using any amount of 15w50 racing oil in it.
 
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there are 2 versions the black plastic bottle and the metal container.

since this is all hypothetical and you wont even give an application I am sure mixing the 2 and burning it in the oil burning furnace would work fine.

If for example it was to be used in a 2020 toyota tundra.. well those spec 0w20? so I wouldnt recommend using any amount of 15w50 racing oil in it.

As stated, there is NO application as of yet. It was for clarification purposes only. This thread isn't an advertisement opportunity for your oil. There is a section for that.
 
As stated, there is NO application as of yet. It was for clarification purposes only.
If I posted
Thick vs thin oil discuss for hypothetical application i wont reveal.
I'd get roasted.. just saying.. this thread isnt far off from that.
we have a search feature that actually works now. might want to go reread some of the previous threads about mixing oils.
the answer is no one knows for certain except that they may not perform as well as not mixing.
Since the additive packages can be slightly or vastly different.
 
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You have no frame of reference for what you espouse. I have been around here since 2006, when Gary Allen was my initial Amsoil rep. Cheers big boy!
 
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