With the great help from everyone on this forum I have narrowed my next 72" deck zero turn to a Ferris 5100 with the Cat Diesel or their 3100 with the 36HP Vanguard. The dry weight difference is 2200 pounds vs. 1400. I would much prefer to go diesel because we have a diesel tank on the farm and the pain of hauling gas cans is eliminated. However I am concerned that the much higher weight of the 5100 will create ruts in the yard when the soil is damp as it has essentially the same size tires as the lower weight 3100. We currently cut with a 72" Dixie Chopper, weight 1300 lbs. and have not had a rutting problem in all types of soil conditions. Has anyone used a 5100 shortly after a rain in clay type soils and had a problem with rutting? Does the extra 800 pounds have any other significant effects like slower to maneuver, etc. Would really appreciate anyones insight on this decision.