I have a troy built riding mower that I need to replace the tire. The model is a Y609H and is about 5 years old and I have not removed the wheels ever. I have removed the plastic cap and the bolt but it seems as though the rim is stuck on the axle. Any help would be appreciated.

This is a very common problem. Try spraying some good penetrating lube onto the axle and then CAREFULLY, AND LIGHTLY take a bar and hammer and put the bar to the inside edge of the rim against the center and tap, rotate a little and tap, be careful not to knock the unit off the supports holding the unit up though. And don't hit to hard, if you do, you can knock the axle loose and have to pull the transaxle and repair it as well.

Thank you for the information , I will try this