Originally Posted By: OVERK1LL
MRV of M1 5w40 is 25,400 cST at -35C.
MRV of M1 0w40 is 26,242 cST at -40C.
It obviously has superior cold performance.
I cannot find an MRV data on the 15w50, so we'll have to suffice with these values and the Widman calc ones:
M1 0w40:
cST at 40C: 78.3
cST at 100C: 14
Density at 15C: 0.85
M1 5w40:
cST at 40C: 100.4
cST at 100C: 14.9
Density at 15C: 0.85
M1 15w50:
cST at 40C: 131.2
cST at 100C: 18.1
Density at 15C: 0.87
Widman's calc data:
Code:
GRADE -35C -30C -25C -20C
0w40 11308.5 6706.5 4135.4 2641.8
5w40 32292.6 17380.1 9818.5 5795.1
15w50 49794.3 26423.4 14724.5 8576.4
I know Doug does not put a lot of stock in the validity of the numbers below 0C, but it does give us some points of reference.
I have PERSONALLY experienced the difference between the 5w40 and the 0w40 in my own vehicle this winter. And to say it was substantial would be putting it mildly.
Excellent data, thank you!