I used to run 20w-50 in my Hemi car. It had awesome oil pressure, but the downside was the time it took the pressure to rise when started cold. I didn't like that.....a good 5 seconds for the guage to reach 85#.

So....to make the story short, the only vehicle out of the 5 I have that DOESN'T use 15W40 Rotella is my wifes 07 Charger 3.5 HO.

Makes the trip to the parts store simple !!!