Hi Matt

Cranking speed is often over looked as a cause of starting issues on Common Rail motors. The starter motor should be considered, but I would not jump straight in & condemn it straight off, without doing some basic volt drop checks on the feeds & grounds & of course the battery needs to be proven too.

You might find this useful for reference values....

http://www.picoauto.com/tutorials/ford-focus-hard-starting.html

HTH

Dave