Hey guys I just picked up a 2008 52/23 with 500 hours. When I tested it out on flat ground it worked great. Now that I got it home I tried going up a slight incline and the gas tank and the donaldson filter shake pretty badly. The engine seems to make plenty of power and it's running on both cylinders so i'm thinking it's a hydro issue. I checked some things out and all the bolts seem to be tight, the hydro belt is a little smooth and glazed but other wise seems decent. Any ideas or suggestions on what to check? Also how can I find out if the unit is still under warranty. I should also mention that it does it with the blades disengaged, and the mower seems to track straight.