I have the same problem on a 1994 MTD, I need to replace a bearing. I tried once before when I needed to repair a Flat tire. I found it easier to install a tube with the tire on the mower. Now it must come off to replace the bearing, so I will use a penetrating oil for a couple of days, then if that fails, I will probably try heating the wheel. Seems they do not use Anti sieze on the wheel when they install the wheel. Good luck, I know I will need it.
Bill Harrington
June 2007