Park the fifth wheel in a flat and level parking area. Set the emergency brake on the towing vehicle and place wheel chocks under the non-flat tires of the fifth wheel trailer.
Place the jack under the wheel well of the damaged tire. Find a solid part of the under-carriage where the jack lift plate rests solidly. Jack up the wheel well area of the trailer so the damaged tire is off the ground.
Unscrew the tire's lug nuts with the tire iron. The nuts are attached in the center of the wheel securing it to the hub. Place the nuts to the side.
Pull the damaged tire off the hub and axle. Slide the replacement tire onto the lug bolts and hub. Screw the lug nuts onto the bolts using the tire iron. Tighten as hard as possible.
Lower the jack and remove it from the underside of the trailer. Remove the wheel chocks and resume your travels.