Enterprise,
I rarely see a problem with the HRX HSA transmissions. If the first one was leaking and you are having a problem, it may not have been repaired properly, there should not be a grinding sound at all. This mower is by far superior to any out there. As far as movement, normally it will not move on the first notch and then will barely move when on the second and so on. There may need to be a cable adjustment to get that set right. Take it to your authorized honda repair center and they should take care of everything. Honda is really good about customer satisfaction, and I have replaced maybe 2 of those transmissions in 4 years, and they were for commercial users.