Wipe down machine with a clean soft cloth and a liquid non abrasive cleaner (Simple Green, Ammonia/Water). Remember sweat is the number one cause of rust.
Use a clean soft DRY cloth (towel) and wipe from the front of the treadmill between the belt and running deck to the back of the unit. This will allow the deck to wear slower and to have a belt that will last longer and need to be calibrated less.
Inspect the running belt to make sure it is not moving closer to one side versus the other. If you do not pay attention to this it can ruin an expensive belt easily. Also be sure to keep the power cable clear of any move parts (incline, belt, etc.) and checking for any loose screws.
Vacuum the floor around and underneath the treadmill to prevent dust build up. TIP: You can put the unit at its highest elevation to get under it.
Inspect underneath the running belt. Make sure the deck has a smooth almost melted feel which ensures there is enough wax for the smoothest run. In most cases commercial gyms will inspect weekly, but home users can arrange quarterly based on use.
Wax 101: Most Star Trac treadmills used a powdered wax. To apply sprinkle about 1 full teaspoon in the front, middle and back between the deck and belt. Do this on both sides. Have the powder blown around to give it the best overall coat.
Finish the process wiping the excess off the sides between the belt and side foot rests and walk on the treadmill for about 1 Mile. If you have a unit from Landice, Precor, Cybex, FreeMotion, Matrix or others you may require a special deck lube that would be distributed evenly over the surface of the deck under the belt.
NOTE: Very few treadmills (Mostly Life Fitness) come with a wax system built in that has a reservoir that connects to a spray nozzle. This nozzle is located between the belt and the bottom of the running deck near the back of the treadmill and should be checked for clogs and cleared. Ask you GymStore.com rep if you think you have one of these units.
Turn off the unit and ground yourself (touch hand to metal). Open the top hood of the treadmill (May require removing a few screws). Using a common paint brush, take a vacuum and remove the dust off all of the electronic components and motor. TIP: Canned Air (Keyboards) can be used for an extra level of preventative maintenance to blow out the motor. Dust and carpet fibers kill treadmill electronics and moving parts like bearings, consider using a rubber mat in this instance as well.
NOTE: Some treadmills (Mostly Star Trac) are equipped with DC motors. These motors use something called motor brushes. In heavy us environments these will wear much quicker but in home settings they should last for years. If the brushes maintain the same size then you are good to go for a while longer.
Cleaned and lubricate the lift system. This parts is located underneath the front of most treadmills (Middle on Woodway) and look like a spiral or jagged teeth that grip gears to move up and down. Wipe excess dirt and old grease down and use standard automotive grease (if needed). IMPORTANT : Make sure none of the cloth you use attaches to the incline lift system or it could damage your unit. Spray the elevation screws with standard silicone.
Inspect wheels in front of unit that incline rolls on for proper function. Ensure they are not damaged on being hindered by any objects small or large.