What Is the Best Way to Fix A Treadmill Belt Slipping Problem?

If you have a treadmill and the walking belt is slipping on the machine, what is the best way to fix it? Before you answer, you must answer the question behind the question. That question is: “why is the running belt slipping?” You might wonder why this is important. The reason is that why the belt is slipping determines how you stop the belt from slipping.

A common problem we hear from consumers each and every day is, “I have tightened the belt on my treadmill as tight as it will get and the belt is still slipping…how do I fix it?” First, go pound your head into the wall repeatedly because that will do you more good than you have already done, then loosen the belt back to the original tension if you can remember where it was.

When you can answer why the belt is slipping, then you can determine what to do to fix it. The most common reasons a belt will slip are:

  • The belt needs lubricating. This is the most common reason a walking belt will start to slip. Our favorite is the “no maintenance” treadmills because if you follow those manufacturer instructions, the belt will prematurely wear out causing you to replace the belt years before you would have to do so. Our second favorite is the big recommendation of water based silicone. It works good but it requires that you use it all the time because a water based lube evaporates (I know that it is a shock that water evaporates but it does). Therefore, you find yourself lubing all the time. Our World Famous Lube has a silicone base but also has teflon and other ingredients that actually repel dirt (the second biggest killer of treadmill belts) and only requires an application once every 12 to 18 months.

  • The drive belt is worn out. If you step on the running belt and it stops but the motor is still turning, look at the front roller. If the roller and pulley stops too, the drive belt is worn. Replace it because tightening typically will raise your operating amps up which burns up the motor brushes and puts strain on the controller.

  • The pulley on the roller is loose from the press fit on the roller’s metal tube. If the roller stops when you step on the walking belt but the pulley keeps turning, you need to either secure the pulley or replace the roller. I take Liquid Paper and draw a white line from the plastic part of the pulley on to the metal roller tube. Then I make it slip. If the line no longer matches up, the pulley is loose. You can either drill a pilot hole and use a very short sheet metal screw to fasten the pulley or replace the roller.

  • The tension bolts (usually rear roller bolts) are pulling through a plastic endcap. This is a very common problem mainly on cheaper treadmills. If plastic parts are used to tension the belt, the bolts used to increase and decrease tension can pull through the plastic when the plastic gets fatigued and then you can no longer tighten the bolts enough. Either use a fix kit where we overlay the original plastic with a metal kit or replace the endcaps. If you want a permanent solution, use our fix kit.

  • The walking belt is worn out. Walking belts eventually wear out. If everything else checks out and lube either doesn’t help or actually makes the slipping worse, replace the belt.