Looking at the spec. sheets, I just realized something.
0w-40 has a viscosity of 80cSt.
10w-30 has a viscosity of 62cSt.
How is this possible...shouldn't 0w-40 be thinner at 40C than 10w-30? What am I missing here?
Even simpler - the 5w and the 0w have NOTHING to do with the viscosity at 40 C.
The 5w must pass a cold crank simulator test at -30 C and a pumping test at -35 C. The 0w must pass a cold crank simulator test at -35 C and a pumping test at -40 C (Standards set up in the J300 testing protocol).
At some point, the lines on the viscosity/temp graph will cross, but it will generally be well below 40 C where this happens.
[ September 24, 2003, 06:16 PM: Message edited by: MNgopher ]