Question about oil viscosity

[Swift101]

Hey Everyone,

I was comparing the two VOAs below and noticed something interesting. I'm not sure if I'm reading this correctly, but is Mag 1 5W-40 actually "thinner" than Mobil 1 0W-40?

Mobil 1 0W-40 https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2365762

Mag1 5W-40 - https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2830961

Also check out Mag1's specs: http://mag1.com/ProductDetails.aspx?id=feb26b17-c445-4631-ac06-5f688312182f

I has a pretty impressive pour point of -45C.
(Note, this is the euro version)

 

[MolaKule]

No, they are both SAE 40's.

 

[Jasper8146]

Based on those numbers, the MAG1 5W-40 indeed does appear to be thinner than the Mobil 1 0W-40. Interesting. Thanks for posting. That MAG1 appears to be one of the thinnest 5W-40's I've seen.

 

[MolaKule]

Send both oils to three more labs and I bet you will see a convergence to 13.0 cSt@100C on both oils.

 

[Boxnuts]

Despite the slightly higher VI by the time you get down to 0°C the Mobil 1 0W-40 is 563 cSt and the Mag 1 5W-40 is 645 cSt so it's now a bit thicker, which is probably what you would expect.

 

[Quattro Pete]

Originally Posted By: Swift101
Hey Everyone,

I was comparing the two VOAs below and noticed something interesting. I'm not sure if I'm reading this correctly, but is Mag 1 5W-40 actually "thinner" than Mobil 1 0W-40?

At 100 deg C, yes.

 

[CATERHAM]

Actual operational viscosity at normal operating Temp's correlates firstly to HTHSV and secondly the oil's VI.
If Mag1 has a HTHSV significantly lower than 3.85cP, say 3.6cP then yes it is a lighter oil, not necessarily on start-up but at normal operating Temp's and higher.

 

[wemay]

Just as some 10w30's are thinner than some 5w30's at operating temps...

 

[CATERHAM]

Originally Posted By: wemay
Just as some 10w30's are thinner than some 5w30's at operating temps...

By "thinner" you mean a lower kinematic viscosity but that's a result of the lower polymer content of the 10w30.
But the 10w30s actual operational viscosity will be higher due to it's lower VI and even more so if it's HTHSV is higher which is often the case.

 

[Swift101]

Thanks for input everyone, I may experiment with Mag1 since it appears to be a light 5W-40.