This is on a bone stock 5.9 Magnum motor I picked up to replace the tired one in my 2000 Dakota. My intentions was to run it "as is" with a valve job on my heads. I haven't seen quite an "distinctive" wear on the cam before. Maybe it's the dark oil that makes it stick out? Obviously, the previous owner didn't change the oil at intervals. Thoughts? I really don't want to tear in the motor.