We have a new oil spec that rates Viscosity in cst at -40c and -48C and I'm having a hard time finding the equivalent SAE rating. I havent seen many oils on the shelf rated at these temperatures usually it is at 100C and 40C. The Viscosity at 100C corresponds to a 20 weight though. Any ideas?
Viscosity ratings and SAE equivalent
- Thread starter metroplex
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If you're rating viscosity of an oil at -40 C and -48 C, you're not going to be able able to do anything, as far as I can figure, to get an SAE rating out of that, since we know where those are measured, and that's 140 C warmer. -40 C and -48 C are often below both the pumpability and pour points of ordinary oils, so trying to extrapolate that to an SAE viscosity strikes me as a fool's errand.
An ordinary viscosity calculator begins to come off the rails when you hit 0 C, let alone -40 C or -48 C. So, you have to compare apples to apples with a KV 100.
An ordinary viscosity calculator begins to come off the rails when you hit 0 C, let alone -40 C or -48 C. So, you have to compare apples to apples with a KV 100.
I understand but I tried to get them to explain why they developed the spec for -40C and -48C when industry rarely publishes those viscosity ratings. They claim it was for arctic conditions, but I pointed out most modern synthetics have a pour point that goes down to about -55C (same as this oil spec) so why omit the viscosity at 40C? At KV100, it is about a light to mid 20 weight oil (ASTM D445).
The SAE rating for 0W is based on a test performed at -40C. That's probably as close as you are going to get when it comes to SAE.
Is it an engine oil that you are talking about ?
Engines would have block heaters and whatnot to ensure that there was something there at the start.
Arctic hydraulic oils have KV-40...
http://tdc.ge/wp-content/uploads/2014/03/18_Tellus_S4_VX_32.pdf
Engines would have block heaters and whatnot to ensure that there was something there at the start.
Arctic hydraulic oils have KV-40...
http://tdc.ge/wp-content/uploads/2014/03/18_Tellus_S4_VX_32.pdf
Originally Posted By: metroplex
Do you have a product data sheet for a D445 test at -40C? I checked some 0w30 oils and all they test down to is 40C for the D445 KV.
MRV is a dynamic viscosity. So, you obviously can't just take one testing method and very easily extrapolate it to something else. Shannow's link is the only one off the top of my head that I recall showing a KV at a weird number. Other hydraulic oils might, perhaps, too.
Do you have a product data sheet for a D445 test at -40C? I checked some 0w30 oils and all they test down to is 40C for the D445 KV.
MRV is a dynamic viscosity. So, you obviously can't just take one testing method and very easily extrapolate it to something else. Shannow's link is the only one off the top of my head that I recall showing a KV at a weird number. Other hydraulic oils might, perhaps, too.
Originally Posted By: metroplex
Do you have a product data sheet for a D445 test at -40C? I checked some 0w30 oils and all they test down to is 40C for the D445 KV.
It's a low temp pumping viscosity test based on ASTM D4684. It's not the same as kinematic viscosity, if that's what you're after, but it's part of the SAE viscosity grading system, nonetheless.
See page 8 of this doc:
https://www.infineum.com/media/80723/api-engine-oil-classifications.pdf
Do you have a product data sheet for a D445 test at -40C? I checked some 0w30 oils and all they test down to is 40C for the D445 KV.
It's a low temp pumping viscosity test based on ASTM D4684. It's not the same as kinematic viscosity, if that's what you're after, but it's part of the SAE viscosity grading system, nonetheless.
See page 8 of this doc:
https://www.infineum.com/media/80723/api-engine-oil-classifications.pdf
That link should be a sticky, Quattro Pete.
Did they list any builder approvals or other numbers or specs we could go by?
Originally Posted By: metroplex
They did post a spec for the ASTM D5293 at -35C and it's very close to the synthetic 0W-20's I found on commercial websites. So it looks like a synthetic 0W-20?
Well, if it tested below 6,200 cP @ -35C on ASTM D5293 and below 60,000 cP @ -40C on ASTM D4684, then it qualifies as a 0W-.
Kinematic viscosity at 100C will determine if it's an Xw-20 or something else.
They did post a spec for the ASTM D5293 at -35C and it's very close to the synthetic 0W-20's I found on commercial websites. So it looks like a synthetic 0W-20?
Well, if it tested below 6,200 cP @ -35C on ASTM D5293 and below 60,000 cP @ -40C on ASTM D4684, then it qualifies as a 0W-.
Kinematic viscosity at 100C will determine if it's an Xw-20 or something else.
Impressive.
What is it at 100C?
What is it at 100C?
That is sounding like a 20, but that's not exactly easy to find as a diesel oil.
at -40° that should be plenty.
Originally Posted By: metroplex
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
Originally Posted By: A_Harman
Originally Posted By: metroplex
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
15,000 at -40C and 50,000 at -48C
Word has it they are looking to replace non-synthetic 15w40 with this new oil.
Originally Posted By: metroplex
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
15,000 at -40C and 50,000 at -48C
Word has it they are looking to replace non-synthetic 15w40 with this new oil.
Originally Posted By: metroplex
Originally Posted By: A_Harman
Originally Posted By: metroplex
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
15,000 at -40C and 50,000 at -48C
Word has it they are looking to replace non-synthetic 15w40 with this new oil.
That viscosity seems to fit the doubling rule: at -45C it would be 30,000, and -50C it would be 60,000. So 50,000 at -48 pretty much follows the curve.
It would be a great oil for arctic use, but I wouldn't want to run it over about 80C in an engine designed for a 40-weight.
Originally Posted By: A_Harman
Originally Posted By: metroplex
It's 4300 at -35C for D5293, and 13,000 at -40C for D4684
I'm curious: What is the viscosity of this oil at -48C?
We have a rule of thumb on BITOG that every 5C of cooling doubles the cold cranking viscosity.
15,000 at -40C and 50,000 at -48C
Word has it they are looking to replace non-synthetic 15w40 with this new oil.
That viscosity seems to fit the doubling rule: at -45C it would be 30,000, and -50C it would be 60,000. So 50,000 at -48 pretty much follows the curve.
It would be a great oil for arctic use, but I wouldn't want to run it over about 80C in an engine designed for a 40-weight.
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