"Motor Oil By AE Haas" , http://63.240.161.99/motoroil/index.html
He mainly concerns himself with viscosity-related questions. The essence of his message can be summarized as :
-- During cold startups (even in mild climates), the inability of thick oil to quickly flow into all the bearings creates the highest risk of increased wear.
-- Therefore, use multi-grade oils with a 'cold weight' as low as practical, eg 0W or 5W.
-- The high end of a multi-vis oil weight should be chosen mainly to achieve desired oil pressure with the engine at normal operating temperature.
-- "weight" grading is a drastic oversimplification of how oils really function across the temperature range. Even for the same nominal weight, synthetics will be thinner and flow easier on a cold start, than will conventional oils.
For example, an oil rated at 5W-30 or even 0W-40 might be the preferred oil based on this line of reasoning.
I'm unable to independently verify everything the author claims, but the main thrust of his arguments seems reasonable. The author does not address at all, the issue of zinc content and cam wear.
Overall this suggests, but certainly doesn't prove, that an "ideal" oil package might consist of :
-- synthetic base
-- 5W-30 or 5W-40 or even 0W-40 weight
-- GM EOS (engine oil supplement) added to increase Zinc levels to about 0.15% (typical of the diesel and "racing" oils).
I note that Shell Rotella-T Synthetic diesel oil is rated 5W-40, but the data sheet doesn't list Zinc content.
Chevron markets Delo 400 Synthetic diesel oil in 0W-30 and 5W-40 grades, and Zinc is specified at 0.13% and 0.15% respectively. This could be the hot ticket.
I'm sure this will incite a lot of heated debate
He mainly concerns himself with viscosity-related questions. The essence of his message can be summarized as :
-- During cold startups (even in mild climates), the inability of thick oil to quickly flow into all the bearings creates the highest risk of increased wear.
-- Therefore, use multi-grade oils with a 'cold weight' as low as practical, eg 0W or 5W.
-- The high end of a multi-vis oil weight should be chosen mainly to achieve desired oil pressure with the engine at normal operating temperature.
-- "weight" grading is a drastic oversimplification of how oils really function across the temperature range. Even for the same nominal weight, synthetics will be thinner and flow easier on a cold start, than will conventional oils.
For example, an oil rated at 5W-30 or even 0W-40 might be the preferred oil based on this line of reasoning.
I'm unable to independently verify everything the author claims, but the main thrust of his arguments seems reasonable. The author does not address at all, the issue of zinc content and cam wear.
Overall this suggests, but certainly doesn't prove, that an "ideal" oil package might consist of :
-- synthetic base
-- 5W-30 or 5W-40 or even 0W-40 weight
-- GM EOS (engine oil supplement) added to increase Zinc levels to about 0.15% (typical of the diesel and "racing" oils).
I note that Shell Rotella-T Synthetic diesel oil is rated 5W-40, but the data sheet doesn't list Zinc content.
Chevron markets Delo 400 Synthetic diesel oil in 0W-30 and 5W-40 grades, and Zinc is specified at 0.13% and 0.15% respectively. This could be the hot ticket.
I'm sure this will incite a lot of heated debate
