Does anyone know how to make comparisons of cold temperature performance of 0W oils when manufacturers publish MRV and others publish pour point? For example, Mobil publishes both for their 0W-30, but only MRV for 0W-40.
How to compare MRV to pour point?
- Thread starter BerndV
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I don't think you can. Those tests measure two totally different things.
MRV measures pumpability, pour point is the temperature at which it loses flow characteristics.
MRV measures pumpability, pour point is the temperature at which it loses flow characteristics.
Pour point isn't considered so relevant.
Yes ignore PP it's missleading at best.
The cold cranking CCS spec' which is measured at -35C for 0W oils is relevant.
The cold cranking CCS spec' which is measured at -35C for 0W oils is relevant.
So there is no way to compare the performance of two different 0W oils at very low temperatures unless we are given the CCS viscosity by the manufacturer. Mobil doesn't disclose CCS for any of it's products and provides MRV only for their 0W oils. Amsoil gives CCS but not MRV for it's 0W oils. Shell, OTOH, gives both. SN Ultra sure looks impressive.
MRV is the most useful spec'.
Shell does provide MRV for their 0W oils.
Mobil is considered to have the lightest (lowest MRV spec's) of any PCMO 0W-20 (9,200cP) and 0W-30 (13,250cP).
Same applies to their HDEOs.
Shell does provide MRV for their 0W oils.
Mobil is considered to have the lightest (lowest MRV spec's) of any PCMO 0W-20 (9,200cP) and 0W-30 (13,250cP).
Same applies to their HDEOs.
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
Originally Posted By: 147_Grain
Keep in mind that the 31,000 cP was at -40*C. cP (ASTM D4684).
All MRV tests for 0W oils are performed at -40C. I was comparing it to their 0W-20 and 0W-30.
Keep in mind that the 31,000 cP was at -40*C. cP (ASTM D4684).
All MRV tests for 0W oils are performed at -40C. I was comparing it to their 0W-20 and 0W-30.
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
Yes the MRV of the SN M1 0W-40 isn't great.
The lighter PAO based SM M1 0W-40 that we still get in Canada has a much lower MRV of 21,000cP IIRC.
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
Yes the MRV of the SN M1 0W-40 isn't great.
The lighter PAO based SM M1 0W-40 that we still get in Canada has a much lower MRV of 21,000cP IIRC.
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
Originally Posted By: 147_Grain
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
How do you know that the best attributes of each oil is the dominant feature at each temp extreme?
Maybe the M1 0W-40 is the dominant oil at very low temps and the TGMO is doing the lubrication at the high temp end, and you are slowly murdering your engine!
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
How do you know that the best attributes of each oil is the dominant feature at each temp extreme?
Maybe the M1 0W-40 is the dominant oil at very low temps and the TGMO is doing the lubrication at the high temp end, and you are slowly murdering your engine!
Originally Posted By: threeputtpar
Originally Posted By: 147_Grain
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
How do you know that the best attributes of each oil is the dominant feature at each temp extreme?
Maybe the M1 0W-40 is the dominant oil at very low temps and the TGMO is doing the lubrication at the high temp end, and you are slowly murdering your engine!
Firstly both oils are completely miscible with each other so the blend will still be a 0W oil. To paraphrase Mobil, "you won't know what the MRV of a blend of both oils will be without testing. All one can say is that it will have a value at some point between the two oils."
Secondly, at the high temp' extreme, the blend has had a number of UOAs done so we know what the resulting viscosity is and how it performs in service.
Originally Posted By: 147_Grain
Originally Posted By: BerndV
Mobil 1 0W-40 at 31,000 cP is quite a bit more viscous than their other 0W offerings.
This is why I cut the 0W-40 with TGMO 0W-20 to get the best of both worlds: high oil temp protection with the 0W-40 and a much thinner oil (0W-20) for improved flow at start-up.
How do you know that the best attributes of each oil is the dominant feature at each temp extreme?
Maybe the M1 0W-40 is the dominant oil at very low temps and the TGMO is doing the lubrication at the high temp end, and you are slowly murdering your engine!
Firstly both oils are completely miscible with each other so the blend will still be a 0W oil. To paraphrase Mobil, "you won't know what the MRV of a blend of both oils will be without testing. All one can say is that it will have a value at some point between the two oils."
Secondly, at the high temp' extreme, the blend has had a number of UOAs done so we know what the resulting viscosity is and how it performs in service.
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