I've got a 2017 Troy Bilt Hydro Horse, I'm trying to find some info on checking & or replacing the oil in the hydrostatic transmission, Troy Bilt was no help after 5 phone calls, they said no info on the trans, can't even tell me who makes....Really!? So, does anyone know how to complete the process or know of a website or manual I can get to show the servicing process, Thanks in advance for any help!!