mixing oil to change the grade
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You can bet that the KV100s (that define the "40", "50", or "30") will be close to a calculated ration.
Can't tell squat about the "W" part of it, other than what it could likely be...probably better than the 15W, and probably worse than the 5W, so probably something like 10W.
Can't tell squat about the "W" part of it, other than what it could likely be...probably better than the 15W, and probably worse than the 5W, so probably something like 10W.
What you do is find out the viscosity of the oils you want to mix and then decide on a target viscosity. Then run the numbers through a viscosity calculator. It's easy.
Not that easy, because you can't predict how different VIIs will interact, and different PPDs, with each other and with different base oils. You may find that the blend does not meet any prescribed SAE viscosity classification, since it has to meet KV, CCS, HTHS and MRV requirements, any one of which could go out-of-spec.
Originally Posted By: Merkava_4
What you do is find out the viscosity of the oils you want to mix and then decide on a target viscosity. Then run the numbers through a viscosity calculator. It's easy.
The problem is the "W" part, as Shannow mentioned.
What you do is find out the viscosity of the oils you want to mix and then decide on a target viscosity. Then run the numbers through a viscosity calculator. It's easy.
The problem is the "W" part, as Shannow mentioned.
What will a 5w50 do for you that a 5w40 won't?
Originally Posted By: weasley
Not that easy, because you can't predict how different VIIs will interact, ... with each other and with different base oils. You may find that the blend does not meet any prescribed SAE viscosity classification, since it has to meet KV, CCS, HTHS and MRV requirements, any one of which could go out-of-spec.
+1
If you dilute VII enough with adition of lesser VII content oil, those now too sparse polymers, won't work at all, becuse they can't catch close togheter enough, not making an oil barrier of flow anymore. So, a once 160 VI would be a mere 100 VI, so your stribeck would get a plane rampant climb.
Not that easy, because you can't predict how different VIIs will interact, ... with each other and with different base oils. You may find that the blend does not meet any prescribed SAE viscosity classification, since it has to meet KV, CCS, HTHS and MRV requirements, any one of which could go out-of-spec.
+1
If you dilute VII enough with adition of lesser VII content oil, those now too sparse polymers, won't work at all, becuse they can't catch close togheter enough, not making an oil barrier of flow anymore. So, a once 160 VI would be a mere 100 VI, so your stribeck would get a plane rampant climb.
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Originally Posted By: Pontual
Originally Posted By: weasley
Not that easy, because you can't predict how different VIIs will interact, ... with each other and with different base oils. You may find that the blend does not meet any prescribed SAE viscosity classification, since it has to meet KV, CCS, HTHS and MRV requirements, any one of which could go out-of-spec.
+1
If you dilute VII enough with adition of lesser VII content oil, those now too sparse polymers, won't work at all, becuse they can't catch close togheter enough, not making an oil barrier of flow anymore. So, a once 160 VI would be a mere 100 VI, so your stribeck would get a plane rampant climb.
Its the WARM part of the envelope that gets most messed up, not the (cold) W part. The W part is made mostly by the base of the lubricant, but the warm operation aspect is given by the VII additive. Conclusion, you can easily calculate the W part with aritmetics, but the hot part is unpredictable. In this case you'd have a 10W??
The pour point depressants messing, won't be so critical as The VII, in this mix case.
Originally Posted By: weasley
Not that easy, because you can't predict how different VIIs will interact, ... with each other and with different base oils. You may find that the blend does not meet any prescribed SAE viscosity classification, since it has to meet KV, CCS, HTHS and MRV requirements, any one of which could go out-of-spec.
+1
If you dilute VII enough with adition of lesser VII content oil, those now too sparse polymers, won't work at all, becuse they can't catch close togheter enough, not making an oil barrier of flow anymore. So, a once 160 VI would be a mere 100 VI, so your stribeck would get a plane rampant climb.
Its the WARM part of the envelope that gets most messed up, not the (cold) W part. The W part is made mostly by the base of the lubricant, but the warm operation aspect is given by the VII additive. Conclusion, you can easily calculate the W part with aritmetics, but the hot part is unpredictable. In this case you'd have a 10W??
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Just because the oils can mix (miscible) does not mean there won't be problems with the resulting mixture. You might want to consider leaving the mixing and matching of ingredients to those that blend them and spend your efforts somewhere else. The oil in that bottle is the result of a lot of technology and knowledge that may not be available to those like you and me. I use an engine oil straight up with no additives and trust that the people that figured out the mix did their job.
Originally Posted By: Shannow
You can bet that the KV100s (that define the "40", "50", or "30") will be close to a calculated ration.
Can't tell squat about the "W" part of it, other than what it could likely be...probably better than the 15W, and probably worse than the 5W, so probably something like 10W.
I agree, for colder climate the "W" part is critical. For Southern California, we almost never have temperature below freezing, no more than few nights a decade, the "W" part is not importance.
0Wxx or 5Wxx or 10Wxx don't do squat when the cold start is in the 40F or 50F.
The oil specs of my E430 is M1 0W40(MB list 229.3 or 229.5), I tried PP 5W20 and Chevron Delo 15W40 some years ago. All 3 difference grades didn't make any different for cold start when temp dipped to low 4xF.
You can bet that the KV100s (that define the "40", "50", or "30") will be close to a calculated ration.
Can't tell squat about the "W" part of it, other than what it could likely be...probably better than the 15W, and probably worse than the 5W, so probably something like 10W.
I agree, for colder climate the "W" part is critical. For Southern California, we almost never have temperature below freezing, no more than few nights a decade, the "W" part is not importance.
0Wxx or 5Wxx or 10Wxx don't do squat when the cold start is in the 40F or 50F.
The oil specs of my E430 is M1 0W40(MB list 229.3 or 229.5), I tried PP 5W20 and Chevron Delo 15W40 some years ago. All 3 difference grades didn't make any different for cold start when temp dipped to low 4xF.
I used to be a crazy mixer but after some unexpected results I have really toned it down. I only mix within brand and type these days. For example my next Jeep oci will be a jug of PHM 5w30 with 1 qt of PHM 10w40.
And the current fill in your Jeep is SAE 30 with MMO, according to your sig, and the end result is?
A little lighter SAE 30, fine for summer. I do generally use a thicker oil when adding MMO although I'm not sure it is necessary. With SAE 30's higher HTHS I wasn't concerned about it though.
Straight grades work surprisingly well in the summer months.
Straight grades work surprisingly well in the summer months.
I was thinking in terms of using different grade of the same brand and type.
I have used 10w50 in my motobikes. I like the 50 because the engine runs hot in the summer traffic jams. going to 5w would help with winter starting and warming up period.
example silkolene pro 4+: 5w40 + 10w50
just curious
I have used 10w50 in my motobikes. I like the 50 because the engine runs hot in the summer traffic jams. going to 5w would help with winter starting and warming up period.
example silkolene pro 4+: 5w40 + 10w50
just curious
Originally Posted By: bonjo
I was thinking in terms of using different grade of the same brand and type.
That would be my suggestion and will likely yield the most predictable result.
I was thinking in terms of using different grade of the same brand and type.
That would be my suggestion and will likely yield the most predictable result.
Originally Posted By: bonjo
interested to find out if I can create a new grade by mixing different grades of the same oil brand and type.
example 15w-50 + 5w-40 in 50/50 ratio to get 5w-50
???
You could just pop round to Supercheap and buy a 5W-50, but what would be the fun in that?
I mix only to use up leftovers and only for warm weather use in a beater since the grade that you actually get is impossible to predict.
interested to find out if I can create a new grade by mixing different grades of the same oil brand and type.
example 15w-50 + 5w-40 in 50/50 ratio to get 5w-50
???
You could just pop round to Supercheap and buy a 5W-50, but what would be the fun in that?
I mix only to use up leftovers and only for warm weather use in a beater since the grade that you actually get is impossible to predict.
I'll mix to come up with a "closer" viscosity to recommended than either of the oils on hand... I'm mixing M1 0W-40 with 5W-20 to come up with a 5W-30(at least close enough)... Chances I'm going to agonize over .5 cSt one way or other are zero & none, there is more variance between brands...
I am looking into this mostly for my motorbike which run much higher rpm, engine temp and has a wet clutch. So much more demanding on the oil than normal car.
IN my car I use Mob 1 0/40 FS since day one, extremely happy with it and not planning to do any oil mixing
IN my car I use Mob 1 0/40 FS since day one, extremely happy with it and not planning to do any oil mixing
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