I have switched my young 4.3L Blazer that sees fleet use to Maxlife Blend and have been very happy with the quietness of the engine and slowing of the cooler line leaks. I have always used 5w30 as per the owners manual & I am about to do an oil change for the summer and am wondering if I will see any benefit by switching to 10w30. After looking at the product specs on Valvoline's website they seem to have near matching numbers in every category except the 5W30 has a higher Viscosity Index rating of 163 vs. 10W30 146. This leads me to believe that the 5W30 might actually even be better period. Your thoughts?
thanks
thanks