When they first debuted the Pentastar, they went with 5W-30 to cover their butts because it was a brand new design. Once they had the customers beta test it and they started to get data and fix the problems, the change to 5W-20 was made.
So yes, it was 100% CAFE driven after they had concluded that the warranty liabilities would be less than the CAFE penalty. Can you tell I'm an accountant?
Perfect analogy. Absolutely stellar actually.
Chrysler has figured that the warranty claims will cost less than the CAFE credits.
Op. honestly I have had a very hard time coming to the whole 20 grade view however I've got an 05 dodge ram hemi. I have the service records from new. It got dealer bulk 5w-20 it's entire life which now stands at 270000kms on the odo and I can honestly say that this truck will still rip all 4 tires off and doesn't consume any oil between changes that I've noticed.
I even used M1 afe this winter which is very thin,for our -40 months,and it didn't consume any,nor made any extra audible noise.
So unless you are the 1% that absolute abuse their engines and may require a slightly heavier grade of oil then I suggest using what Chrysler tells you to use. It hasn't done any harm in my high mile hemi. In fact this test mule has me believing in thinner oil now,at least in applications that call for it.
Use with confidence and expect a long reliable life from your equipment.