Crunching noise coming from left track drive

Hello all. Just got my hands on a jd ct332 2006 last week. So far I have put about 15 hours on it and blew out one of the hyd lines to the left hand drive motor. Had John Deere shop make me two more so I could replace both hoses while I was getting greasy anyway. Cranked up, checked for leaks and all looked good until I started making a right turn. That's when I heard a crunching noise coming from that side, which also caused the machine to bog real bad. With my brothers watching that side of the track, I backed up so we could make sure there was nothing binding the track. The track seemed to move normal in reverse, but go forward and it bogs the engine again. I shut machine down, got out and put my hand against the gear housing which felt not hot enough to burn your hand, but way hotter than the right side. I want to start removing the track to get to that side to remove the drive system but after reading all the posts about rebuilding/replacing drive motors, I just wanted to know if I should simply replace the drive motor, which my brother and I am very capable of doing, or do we need to flush the entire hydraulic system. The machine was stuck in the mud before the hyd lines blew, but I had been running it about an hour after getting it unstuck. By the way, tool_king, thank you much for the service manuals. I did not know if my e-mail response had gotten back to you or not. Thanks all for any help.