I have a 2005 F350 6.0 dually that is giving strange starting patterns. When turning the key sometimes it turns over like it's on adrenaline and other times it acts like the batteries are going dead. When it turns over slowly like it's dying it will eventually speed up and have full cranking potential. This morning it started cranking slow and then completely stopped, now when you turn the key there's no clicking sound or anything. Both batteries are above 12v on the meter. I tried the yellow/blue line wire and got no results. Just looking for some input before I dump $ into a starter.