You can go here and download your service manual,
second block down, left side, second line.
page 30 describes belt change procedure.
https://www.ccpartsnmore.com/cub-cadet-service-manuals

You can go here and download the hydro service manual,
https://www.hydro-gear.com/download/...27af1750701849

thanks seems like low hours to me, and they are non serviceable
so Ill keep searching to see of someone has
"been there done that" :bigthink:

thank you, that will help

Ironman -
so the manual shows a steering wheel model , but I assume that all the rest of the manual applies ? Mine has the push arms?
The belt R/R seems pretty strait forward in the manual

I suggested that manual because you said it is circa 2017, but you can look at earlier lever models from the same link to see if it is more appropriate.
If you look at page 34 for the S model, they do mention a worn belt could cause your problem.

Ironman and George are right. that hydro is well on its way to complete failure. they consist of a bi directional piston pump and hydro motor. the hydro oil gets hot and thins out, then it leaks past the erosion in the metal parts reducing its efficiency and finally cannot make motion. it cools quickly gains viscosity and will work marginally until it gets hot again. I have rebuilt a few of the unrebuildable units with limited success like 1 in 5! the problem is in many of the failed units -the part that is worn out is typically the housing - this is the pump discharge valve surface. basically the high pressure oil in the cylinder, headed to the motor, can escape to the reservoir or the next piston/cylinder at lower pressure instead of going toward forward motion. if you choose to open it up you you will see pitting in the ports from cavitation. The forward direction ports usually wears out first because it is used the most. I think I have always had the right side fail first as well. The higher end hydro units dont use the case for sealing or metering of the high pressure oil. because of this, they are completely rebuildable and more expensive. your best bet is gonna be to find a used same model mower or ZTR that used the same hydrotrans unit complete - one with a bad deck or motor and just swap that hydro out. then hope its not worse than what you had.

I've rebuilt a couple and the problem I have found is scoring on the mating surfaces of the Motor Block and Center Section. Yes, the oil gets hot and thins and the scoring lets the pressure escape.
All my rebuilds were successful, trouble is your looking at a couple hundred dollars in parts.

Ill try to source one as I try the belt first, but I agree with you folks, looks like it is destined to die fully

who do you all use for parts , if I can even find one?

and what is considered right , looking from the front or from the back

Left and right is established as the operator is sitting in the operator seat.:beerchug:

I am a bit late to this party and agree whole heartedly with the failure
of the pump theory. I am 99 percent sure of it. That said, in order to
satisfy the other one percent. I have worked on a couple these much
older then yours though.
The handles were adjustable in order to make the pressure put
on the pumps equal as the handles wore. Might take a look at how
your handles attach and how they interact with the pumps.
It's a long shot but it doesn't cost anything.

Ken