I've got a 10 yr old Snapper riding mower. In the past year, the transmission seems to be slipping on loads (like a hill). I replaced the clutch wheel and also adjusted the spring on the clutch to the #1 position without any help. I think it's strange I can put the mower in gear and turn the clutch wheel with my hand.

I'm open to ideas. It's 10 years old but has never given me any problems until this.