I have a Troy-built lawn tractor (model D609G, G609G, U609H or X609G series) which when the shift lever is engaged to FWD or REV it will not move. Is it possible the belt off the Transmission Idler pulley is loose or the cause of the non-movement? What is it that controls the engagement of the transmission? I looked at the belt and it seems intact but I didn't do a deep inspection of the belt... I thought it was still intact. What would be the most likely cause of this so I can pinpoint the problem?

Is the tow valve rod engaged? What about the park brake? Is it released? Have you had either of the rear wheels removed and the wheel to axle left out?

Is the tow valve rod engaged? What about the park brake? Is it released? Have you had either of the rear wheels removed and the wheel to axle left out?

Not sure what the tow valve rod is. The parking brake was released... I went to move FWD like I always do and disengaged the brake but didn't move FWD like I expected. Never removed the rear wheels. I used the mower a week prior and made no changes since. I wonder if the belt could have came loose for the transmission drive and I didn't notice it. I will look for the tow valve in the manuel but I am not sure what you mean by that.

I believe it is a knob on the rear frame that you turn or move on Troy-built. I'm a JD man myself

you may have another drive belt on the transaxle, reach up underneath the rear end and feel to see if you feel a double variable speed pulley that feels as though it has two belts, if the top one is off, it will not move even if the lower belt is still on.

you may have another drive belt on the transaxle, reach up underneath the rear end and feel to see if you feel a double variable speed pulley that feels as though it has two belts, if the top one is off, it will not move even if the lower belt is still on.

I will check the second belt which seems to drive the transmission. I see in my manual that there is a drive belt for the transmission (I knew there were two belts because I replaced them this season). That seems to be what I am up against since it worked last week that I used it. If that doesn't fix it... I will inspect the shift lever some more at the connection. I always get the only mower with problems... :)