I'm sure that this has been discussed many times in the past. Has anybody looked into why the same engine, but different years, requires different viscosity oils.
I have heard some say, well that is what the factory recommends. That is fine, but there has to be a reason for it.............
Are the tolerances tighter on the 3.6 2013 engine?
Is it strictly fuel economy related?
Thinner oil does dissipated heat better so is it a heat related issue?
Has anybody talked with a factory rep to better understand as to why?
One of my concerns is in Phoenix mid summer we see temps radiating off of the asphalt at approx. 165 degrees. 20 weight is a very thin viscosity to lubricate the engine properly at high oil temperatures.