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<DIV><FONT size=2>It's panto season, so "Oh yes there has" (been a lot of
ridiculous debate) and "Oh no there isn't" (a large difference in
viscosity).</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Engine oil and gear oil are measured on different
scales. The viscosity of SAE80 gear oil is 7cSt, which falls between
the viscosity of 20W engine oil at 5.6cSt and 25W at 9.3cSt. SAE90 gear oil is
13.5cSt which falls between SAE40 engine oil at 12.5cSt and SAE50 at
16.3cSt. Also EP 90 gear oil was always specified for the V8, and at one
time for the 4-cylinder as well.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>PaulH.</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
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<DIV>Are you sure it isn't the gear oil?</DIV>
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<DIV>The factory has always called for engine oil. There has been a lot of
ridiculous debate over precisely what grade of engine oil (personally, I don’t
think it matters, but let’s not start that), but there is certainly a large
difference in viscosity between say 20W50, and 85W90. The overdrive, unlike
the rest of the transmission, uses oil in a hydraulic function, not just as
splash lubrication, so viscosity is probably very
important.</DIV></BLOCKQUOTE></BODY></HTML>