Viscosity grade

any of a number of systems which characterize lubricants according to viscosity for particular applications, such as industrial oils, gear oils, automotive engine oils, automotive gear oils, and aircraft piston engine oils. ISO and SAE are the two systems most often encountered in oil analysis applications.

SAE
Viscosity
Grade
“LOW” TEMPERATURE “HIGH” TEMPERATURE
Cranking (cP)
max (°C)
Pumping (cP)
max (°C)
Low Shear Rate
(cSt) 100°C
High Shear Rate (cP)
150°C minimum
min max
0W 3250 (-30º) 60,000 (-40º) 3.8 N/A N/A
5W 3500 (-25º) 60,000 (-35º) 3.8 N/A N/A
10W 3500 (-20º) 60,000 (-30º) 4.1 N/A N/A
15W 3500 (-15º) 60,000 (-25º) 5.6 N/A N/A
20W 4500 (-10º) 60,000 (-20º) 5.6 N/A N/A
25W 6000 (-5º) 60,000 (-15º) 9.3 N/A N/A
20 N/A N/A 5.6 <9.3 2.6
30 N/A N/A 9.3 <12.5 2.9
40 N/A N/A 12.5 <16.3 2.9 (0W-40, 5W-40,
10W-40 grades)
40 N/A N/A 12.5 <16.3 3.7 (15W-40, 20W-40,
25W-40, 40 grades)
50 N/A N/A 16.3 <21.9 3.7
60 N/A N/A 21.9 <26.1 3.7

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