I have a 11 year old Ariens 46 hydrostatic drive mower made by Husqvarna that cuts too short with the deck all the way up against the stops. My lawn is 65 years old with deep thatch. The wheels just sink right down. Been lookin to see if I could find bigger tires that might fit in place of the OEM 20X8X8 and 15X6X6. No luck at all. Any one out there have a solution to this problem? Thanks Frank