Brake adjustment with low pedal
 

98.5' Ram 2500 4X4 Cummins 5speed.
I just installed new front brake pads, Rotors and Calipers were good and dry. Replaced rear brake shoes, wheel seals and installed Chevy one ton wheel cylinders, and bleed the brake system. Truck stops as it should and coasts freely with no brake drag felt. The brake pedal goes almost to the floor, which does not feel correct to me. Could I have a master cylinder or booster problem?