Visual of oil viscosity

William1

Well-known member
Lifetime Member

Equipment
BX25D
Jul 28, 2015
1,218
417
83
Richmond, Virginia
Odd.... I'd expect both 5W to be the same at room temperature. Got to be something off with that test.
A better test would be a drip test. A quart and a tiny hole for each sample and time to drip a quart. Oil rating is viscosity, 'thickness'/ability to flow not film strength. Do this test in a freezer, then again at room temperature then again heated to 180f.