REGARDING SAE viscosity
Lee Daniels is describing the Saybolt Universal test for kinematic viscosity.
It involves a metal tube with a small orifice made to rigid specifications and
calibrated; there is a Universal viscometer for thinner fluids or a Furol
viscometer for viscous fluids like motor oil. The fluid to be tested is poured
through this tube and orifice. The time required for a gravity flow of 60 cc's
of the fluid is called the Saybolt Seconds Universal, or the Saybolt Seconds
Furol. This number can be converted to centistokes if you like. The tester
plugs the number into an SAE chart to see what range it falls in, which gives
it the SAE number. The test is run at 0 deg F (-18 C) and 210 deg F (98.9 C).
The "W" number is from the cold test and the non-"W" number is from the hot
test. Do not compare them, they are unrelated, just range designations, could
have been A,B,C,D. Example: SAE 10W30 and SAE 10W40 fall into the same
viscosity range at zero F, but the 30 is in a thinner range than the 40 when
they're both warmed up to 210 F. SAE 5W50 would be thinner than both at zero,
but thicker than both at 210.
Of course if it doesn't say "SAE", all bets are off.
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