Dodge Truck Oil Filter Replace/Remove

Hi, My Ram Seems To Be Lacking Power, Should The Button For The O/d Be Turned On...it Is Unlit So I Assume It Is Off. Have Changed Dist.cap...

Don't Let The Mileage Scare You. Truck Is On It's Third Engine. Currently Use Castrol 20w-50 And Change Oil And Filter Regularly. Oil...