I've decided to try 5w-50 in my 1988 7.3L diesel (non-powerstroke). It's in great shape, but there's some blow-by + oil consumption that a 50 grade mitigates. I've used Amsoil 20w-50 and 5w-40 (and of course 15w-40). With the 5w-40 there is great low temperature starting, and with the 20w-50 blow-by and oil consumption are minimized. Thinking 5w-50 will be a good choice.
Looking for a 5w-50 with SN & CF rating, here's the contenders so far:
Red Line http://www.redlineoil.com/product.aspx?pid=135&pcid=21
Mobil 1 http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_5W-50.aspx#
Amalie http://www.amalie.com/Passenger-Car-Motor-Oil/Elixir-Full-Synthetic/5W-50
Amalie has the lowest VI (150), so perhaps that indicates less VI improver and less tendency to shear. RL has the highest VI (186) and the highest 100C viscosity (21). M1 and Amalie both have the same 100C viscosity (17.5).
Thoughts?
Looking for a 5w-50 with SN & CF rating, here's the contenders so far:
Red Line http://www.redlineoil.com/product.aspx?pid=135&pcid=21
Mobil 1 http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_5W-50.aspx#
Amalie http://www.amalie.com/Passenger-Car-Motor-Oil/Elixir-Full-Synthetic/5W-50
Amalie has the lowest VI (150), so perhaps that indicates less VI improver and less tendency to shear. RL has the highest VI (186) and the highest 100C viscosity (21). M1 and Amalie both have the same 100C viscosity (17.5).
Thoughts?
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