I recently purchased my 3500 with a 6.0 and the starter made a grinding noise right before it started. I drove it for a while and then it just made the grinding noise and didn't start. I pulled the starter and had it checked out and they said it was fine, however someone looked at it and said it probably was bad and didn't engage all the way out so I purchased a new starter and put it on and same results. Looked at the flywheel and it looks good. Rolled the truck forward in gear, put in a new battery and no difference. Any ideas?