Transmission Question
 

Today, I was cutting grass and about 75% done when I noticed my tractor--GT 2000--would not turn uphill. About 5-10 minutes later, I stopped and finished with my push mower. I was about a half quart low. I got some Cub Cadet drive transmission fluid and filled it up, and it runs better; however, it still screams on hills and will not go up inclines it used to. Tractor has 168 hours on it, and the transmission filter and fluid were changed around 110 hours. Any suggestions or is this a bad sign?

Update:

So I changed the transmission fluid and filter today and noticed the fluid was very dark. Once I was done that, I noticed when going up steep hills I heard a loud chatter. I messed around and found one of the four bolts holding the pump onto the transaxle was coming out nearly a half an inch. Once I tighten this, the chattering went away. Now, I noticed the brake disc is thin and loose (tractor barely stops with brake pedal pressed) and will have to replace it tomorrow. The one thing that is perplexing me is when the bypass valve is pulled (for transport) I can still get on the tractor and press the forward and reverse pedals, and the tractor moves. It never used to do this. I can't understand/see how the bypass valve does anything. Any suggestions?

Update on the update:

I noticed when I had the bypass rod engaged or disengaged the tractor acted the same. I have noticed this since the last time I pushed the tractor out of the garage. Today, I removed the lever and found out just how engaging/disengaging the rod works. I found there was a valve under this lever; however, it would not move. I removed the nut surrounding it which exposed the full length of the vavle and noticed it would only move slightly. I kept pushing it in and pulling it out several times until it released. The new transmission fluid seemed to help loosen it up, and now, it works like a charm. I also learned from watching YouTube videos how to tighten the brakes up. I found the disc brake was not that thin or wore after all. I may have to replace the pads soon, however. Tractor has more zip to it. I think the transmission fluid will need to be changed more frequently as my yard has many hills with areas of wet, swampy grass to areas the are dusty and dry. Does anyone know what transmission fluid can be used in place of the stuff Cub sells as that stuff is expensive? The total cost with filter was over $90.

You can buy 5 gallons of Hy-Tran for less than that.
Where did you get it?

The newer Cubs do not use Hytran. They use some synthetic blend.

I got my stuff at the Cub Cadet dealer. I read Hy Trans was used in older Cubs with the Sundstrand transmissions, but I was not sure it could be in the newer Cubs with Hydro Gear transmissions. If it can and it is cheaper, I may have to go that route.

Thanks Roland.

I think most of the new hydro gears use a variation of engine oil in them. Even my newer skid loader uses 10W30 instead of hydro oil! One pail services the whole dang machine. I think I remember reading in the manual for my ma's mower that it took 20W50 oil in the hydro too. 50 hrs first change then 200 hours after? I think she has a 2138. It's close to that number anyway.
My Gravely zero turn has dual hydro gear in it and I run 20W50 API SJ synthetic in those. I change the oil and filters every other year regardless of hours.

The recommended Hydraulic Fluid is in your Owner's Manual for the model of your tractor.