Model 1405 5 speed transaxle
 

I am looking for some advise on repairing my 5 speed transaxle (Peerless 801-045A) on my model 1405 Cadet. The transaxle will seem to slip or just quit moving while in 2nd or 3rd gear. It may go for 50 or 100 feet then just stop. I can shift into 1st, 4th or 5th and everything is fine. I have been into the transaxle 2 times now and the only thing that I replaced was the shift keys. Everything looks correct by the manual. I wish I had a repair manual that would tell you what to look for. I do have a manual I brought from Cub Cadet for this model but it only shows the parts and breakdown. It says nothing about what could cause problems with this transaxle. Can anyone give me some help or advise? I don't want to sell my Tractor, its been a great piece of equipment until this happened. If no one knows what my problem may be, does anyone have a good used 5 speed Peerless 801-045A transaxle for sell?