I have a 2003 f-350 with the early 6.0L engine. I replaced the starter a year ago due to the starter rod turning but not engaging the flywheel. The new starter did the same thing however it would only do it on cold starts, and after 2-5 tries the starter would engage and start the truck. Also on 80 plus degree days it would start first time even if engine is cold, but if its 50 or below it takes a few tries. I turn key for start and I hear the starter rod spin but not engage flywheel, I will stop for a few seconds and try try try till the starter engages flywheel and it starts. All mechanics i show it to are stumped and i need help, also flywheel was inspected with no issues.