The tractor is a 2005, 740 hours. Not used hard. Was pulling a set of disk and noticed the tractor would spin a back tire. Felt like front wasn't pulling. Raised front end on the bucket and backed up no wheel turn as has always happened when the front wheels were off the ground in 4wd. All linkage moves freely. Shaft coming out of trans moves with linkage. No grinding, No noise, I see a retainer on the shaft and wonder if I can pull it out and maybe something simple has broke. I don't have a manual, If I could just see whats inside. thanks