I have 2 Cub Cadet 1330's with Hydro Drive problems. One went out last year & the other a couple of days ago. Belts are fine. I pulled them both and opened the trans-axle housings. One has a busted Differential Housing Assembly (Part #717-0777) which is a repair I have had to make before, but the other trans-axle appears to be in good working condition. All the gears, splines, etc... are in good condition. I also pulled the Hydro Pump off the trans-axle and checked the splines between the pump & trans-axle & they also look fine. With the unit reassembled, I can turn the drive belt pulley and engage the forward/reverse lever and the axles do engage & turn. Any suggestions?