Determine why the lawn tractor's engine is running poorly or hesitating. First, run the tractor's engine at full throttle. Check the angle of the blade and reposition the blade, raising it if necessary. Also check and adjust the tractor's skid shows.
Inspect why the blade is digging too deeply or not deeply enough. Raise or lower the blade for proper cutting depth. Adjust the skids shoes as well.
Troubleshoot why the tractor's blade is not removing material from the surface. For this problem John Deere recommends installing a squeegee kit (sold separately). A squeegee kit is a rubber fitting encompassing the tractor's metal blade. Use a squeegee blade for snow as well.
Add rear weights to the lawn tractor's backside if the rear tires are slipping and not gaining traction. Add chains to the rear tire treads to gain traction as well.
Consult your local John Deere dealer or distributor for more advanced problems.