Cub Cadet ZRT S back wheel issue

[tootan]

We have a Cub Cadet ZRT S Series zero turn that is just 2 years old. Yesterday is started driving strangely. The right back tire spins faster than the left and is causing ruts in the yard and driveway. Even threw the tractor into a cookie at one point. It runs fine in reverse. Any ideas what could be causing this?

 

[rperk]

either the linkage to the hyd motors are out of wack or the left hyd pump/motor has lost some of its get up and go.
The first can be adjusted ,the second will need repairs