In this video a 2015 Charger R/T owner shows how to change the differential fluid. Watch at the 9:01 minute mark where he shows you the metal gear shavings from the break-in period. It's proof that it's worth changing the fluid early. How to Change Rear Differential Fluid in 2015+ Dodge Charger RT / 392 / Hellcat - YouTube
Here's a correction to the DIY video. Remember to use a torque wrench when tightening the drain plugs. They are steel and the housing is aluminum. The correct torque is 26 foot pounds.
