Treadmill Thump Noise When Running

Every new treadmill will have a thumping noise originating from the walking belt, which is completely normal. This is because the belt is still brand new and stiff. 

You will notice that these disturbing sounds lessen over time as you begin to use the new treadmill.

However, there are a few things you can do in order to get rid of or at least make this sound less annoying. Let’s look at the practical solutions to fix the treadmill thump noise.

Without further ado, let’s get right into it!

Why Is My Treadmill Making Thump Noise?

Horizon treadmill in my garage gym

There are many reasons why your treadmill might be making thump noise. The most common one is usually caused by a poorly lubricated belt. 

However, it may also be caused by walking belt stiffness, or the belt is misaligned and loose.

Stiff Belt

Every new treadmill will have a thumping noise originating from the walking belt. This is because the belt is still brand new and stiff. 

This noise will diminish over time as you start using the treadmill belt quite often. As the walking belt will stretch, causing it to run smoother over the rollers.

Lack of Lubrication

When a treadmill belt is not properly lubricated, it will create a thump sound because of the produced friction. This can lead the drive motor to burnout because of the excessive effort to rotate the belt.

A treadmill which lacks lubrication can also harm the belt and lead to premature degradation. 

The proper lubrication allows the running belt to glide smoothly along without producing such annoying sound. 

Misaligned Walking Belt 

Misalignment on the walking belt is another common cause of treadmill belt thumping sound. This issue usually occurs when the belt is not properly centered. 

When your belt is putting too much friction on either of the rollers because it isn’t aligned properly, the thumping sound can often be heard.

This in turn can cause the running belt to slip to the sides and scrape the edges, which can produce loud thumping or scraping noises. 

How To Stop Treadmill Thump Noise?

There are numerous things you can try to get rid of the thump noises produced by the running belt of your exercise equipment.

But before making any alterations, make sure your treadmill is sitting on a flat, level surface.

white male athlete in gray shirt running on a treadmill

Lubricate the machine

Without proper lubrication, your treadmill’s belt and deck could rub and create too much friction.

On your treadmill, there are various metal on metal pivots points. Over time, they’ll start making an annoyingly thumping sound when they make contact. What you need to do is to lubricate them.

First, lift up the deck to get the treadmill into a folded position, then apply a grease lubricant to all the pivots points down there.

The next thing to do is remove the motor cover. Loosen those Philips screws and then pull the cover off.

After you have access to the incline motor, apply some lubricant grease to the incline pivots.

Next, using the T-wrench or Allen wrench, loosen the rear roller tension bolts 10-15 counter-clockwise turns. This should give the belt enough slack for you to lift it.

Reach under the treadmill belt and use a piece of cloth to wipe it down to ensure it is clean prior to applying any lubricant.

Lift the belt as far as you can, then squirt the silicone oil in a zigzag pattern on one side of the running deck surface. 

Do the same on the other side, using about ½ bottle of silicone lubricant on each Side.

Make sure to not apply the silicone oil on top of the running belt. 

Once you are finished, lay the running belt down and then retighten both rear roller adjustment bolts clockwise the same number of turns loosened.

While staying off of the machine, plug it on and allow it to run at about 3 mph for about 5 minutes, so the lubricant can be evenly distributed.

Once the belt is fully lubricated, make sure it is properly centered and tensioned, then wipe any excess oil from the sides with a damp cloth.

Adjust the belt

picture of a female person using a treadmill

A noisy treadmill belt sound is usually a sign that the walking belt needs adjustment. 

Adjusting the running belt is easy and the only tool needed is the Allen Wrench or Hex Key that came with the machine.

Below are instructions on how to adjust the tread belt and stop the thump sound.

  1. Power down and unplug the Tread. Use the 6mm Allen key from the toolkit that came with your Tread to tighten the Idler Roller Screws.
  2. When tightening the belt, turn both the left and right idler bolts the same distance and direction.
  3. Turn on the Tread and briefly walk and run on the machine to make sure the belt isn’t slipping. 

Prevent over-tightening, which could cause other unwanted issues. You know you have reached the proper tension when the belt lifts about 3 to 4 inches off the walking platform.

Final Thoughts 

There are many reasons that cause a treadmill to start making a noisy thumping sound or other annoying noises. The most common one is usually caused by a poorly lubricated belt. 

Thumping sounds may also be caused by the walking belt stiffness, or the belt is misaligned and loose.

After today’s article, you will be willing to prevent the loud disturbing noises produced by your treadmill machine.