Determining whether your treadmill belt has worn out can be confusing if you don't know what to look for. Cues like fraying edges, discoloration, sluggish belt movement, or a loose "slipping" feeling can all be signs that the belt requires maintenance. To ensure you are replacing the belt as needed due to wear and tear, you need to know exactly what to look for and what tests to perform. Regular maintenance and replacement will ensure safety for you and other users for years to come.
Unplug your treadmill. Loosen your treadmill belt so that you will be able to visually inspect and feel the interior and exterior belt surfaces. Grab the screwdriver that's designed to fit the tension roller bolts. This tension roller is located at the back end of the treadmill belt. Look for the bolts on either side of the treadmill belt at the rear end of the treadmill. Loosen both bolts by turning the screwdriver counter-clockwise. Avoid loosening the bolts too much; you want them just loose enough to be able to slide your hand inside the belt to check for wear and tear, and to be able to visually inspect the underside of the belt.
Feel both sides of the belt. You are looking for any signs that the belt may be experiencing uneven wear, so if you feel excessive smoothness in the areas where you walk, your belt needs to be replaced. Also, if you feel any fraying, cuts, snags or any other significant deformation, these are signs that the belt is compromised and should be replaced.
Identify the seam where the belt has been connected. This is usually a diagonal seam that you can visually identify. Check for any signs of wear and tear on the top of the belt seam. If the edges are fraying or coming apart, you need to replace the belt. Loose seams can come apart and could lead to significant injury or can be a trip hazard for the user.
Run your hand along the seam on the underside of the belt, feeling for any sign that the seam may be wearing, fraying or otherwise coming apart.
Look at the top and the underside of the belt for any discoloration that could be an indicator of excessive wear. This often looks like black or darkened streaks of color. If necessary, use your flashlight to inspect the underside of the belt.
Things You'll Need
Screwdriver designed to fit the roller bolts of your treadmill (consult your owner's manual)
When in doubt, throw it out. A damaged or worn out belt can be dangerous for you and can quickly wear out electrical components of the treadmill. It is better to replace the belt than to risk an injury or more costly repair.
If your belt is running slow, or feels loose, you may assume that the belt needs to be replaced. Often, though, these are indicators of too tight or too loose tension rollers, and can be fixed by either tightening or loosening the tension rollers.