My L4200 GST has 1100 hrs. on it. while driving it I lost power steering one day also forward and reverse gears. After letting it set for several minutes steering returned somewhat and the forward and reverse gears engaged although it took several seconds before engaging. I changed the hydraulic filter and the fluid. I still get marginal steering and several seconds hesitation before engagement in forward and reverse occurs. I sure could use and idea or two, thanks Larry