The John Deere LX172 features a 14-horsepower Kawasaki engine and a five-speed manual transmission. The brakes on a LX172 use a dry brake disk that is also commonly found on cars. When the brake pedal is depressed, it pushes small brake pads against a disk located on the outside of the transmission. As the machine ages, so will the brake pads, making it hard to stop. Knowledge of transmission theory is necessary to complete this task. The procedure will take 20 minutes to complete.
Park the lawn mower on a hard, level surface and set the parking brake. Turn the ignition switch to the "Off" position.
Place a jack under the frame at the rear of the tractor and raise the tractor off the ground; slide the jack stands under each side of the frame directly behind the rear tires. Lower the jack until the frame rests on the jack stands.
Remove the left side tire; pull the cap off the center of the wheel by hand. Pry the snap ring off the axle with the flat-head screwdriver. Slide off the washer and tire to expose the brakes and linkage.
Remove the 10mm nut that holds the brake assembly and pads in place. Make note of how the brake components slide off. Place the new brake pads into place. Reinstall the brake components by referring to the note pad. Tighten down the nut that holds brake assembly in place.
Slide on the tire and washer. Push the snap ring onto the axle. Lower the machine to the ground.