My hydro has seemed to lost its oomf the last couple of days. Roaded it 50 miles, ran fine, even up some good hills, cut wheat for 3 days, and now when I hit the road it seems to stall out on anything but flat ground, can't run the handle full forward very much, and surges a little. It does alot of whining like it is trying, but can't do it, and does drag the RPMs on the engine down some. Is it a filter issue? The reservoir is full, no leaks, and seemed fine 2 days ago. When I go down hill it speeds up some, but reaches the point where the hydro keeps it from running away. Hopefully it isn't something major, because I have to drive it home in a few weeks.