Thank you for the ideas. Have tried lowering the tire pressure to no avail. There is no seat adjustment on the Z254 and swapping springs from my old Z2248 made a world of difference. Some have suggested softer tires but that's expensive. A friend bought a new John Deere zero turn with the...
Thanks for advice from all who replied. In the meantime I got to looking at the seat suspension on my old Z4822 and discovered it actually had springs bolted onto the frame. I never had an issue with its ride so I removed them and transferred them to the new Z254F and tossed the new rubber...