I have a ZD 326S and it has mowed great for the past couple years, all of a sudden I am having an issue in heavier grass, one blade will not cut evenly. At first it was on the left blade and we thought we had dull blades so we changed them. At first it was fine now the center blade is doing it.
I am thingking the issue is with the belt, does anyone have any recommendations?
It sounds like it could be the belt slipping to me. Do you lube the pivot on the tensioner pulley near the rear of the deck on the left side? Its hard to see and easy to miss.