Is ford using dodge cummins motors?

The Cummins motor is not a "Dodge". Dodge does use the "b" series Cummins engine in its pick up trucks. Ford does use the Cummins in its F650 and larger trucks.

NO, Ford never has used the Cummins Diesel as far as I know. Up until 2010 the Powerstroke was built by Navistar, formerly International Harvester. In 2010 Ford starting building the Powerstroke themselves but kept the name. Dodge uses the Cummins diesel and GM uses the Duramax which was designed jointly with Isuzu.