The Pentastar was designed for a 30w from the factory. Sometime around 2013, FCA changed its recommendation down to a 20w...my guess is for CAFE standards. I run a FS 5w30 in both of my engines all year long up here in MN.
If you are considering a 5w20...I would go with my favorite 0w20 and call it a day. Good luck.
If you are considering a 5w20...I would go with my favorite 0w20 and call it a day. Good luck.