Lawn tractor tires, like any other tire, wear out. Most lawn tractor tires are hollow rubber inflated with pressurized air. As you mow your lawn and drive over different types of terrain, eventually the tires will need to be replaced. Replacing the tires will keep your lawn tractor from experiencing other preventable problems. Luckily, because the lawn tractor is small and not that heavy, it is fairly easy to change a lawn tractor tire.
Move your lawn tractor to a hard, level surface. Put the parking brake on to keep it from rolling.
Place a jack under the frame near the tire you want to change. Jack the lawn mower up so that the tire is a few inches off the ground.
Remove the black boot that covers the axle by gently pulling the boot off with pliers.
Use a flat-head screwdriver to remove the "C" clip that holds the tire on the axle. Go slowly on this step to keep the clip from flying off and getting lost.
Let the air out of the tire by unscrewing the valve with a valve stem tool. Screw the valve back in after the air is released.
Use your pry bar to break both the inside and outside beads. Insert it between the rim and the tire and slowly pry the tire away from the rim. Work it around the tire until the bead is broken. Then repeat for the other side of the tire.
Remove the inner tube from the tire if your lawn mower has one. Not all lawn mowers have an inner tube. Work the beads over the rim until the tire is off.
Lubricate the beads of the new tire with tire lube. Position the tire on the rim at approximately a 45-degree angle and push the tire over the rim on that side. Use your pry bar to work the tire on to the rim with gentle pushing and prying actions. Insert the inner tube if your tire uses one.
Wrap a ratchet strap around the tire to hold the beads tight to the rim. Fill the tire with air and remove the ratchet strap.
Push the tire back on the axle and slide the "C" clip into place. Push it on tight with your flat-head screwdriver.
Stretch the black boot and slide it back over the axle. Lower the lawn tractor to the ground and remove the jack.