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If you have a treadmill in your home workout space, you probably know that it takes a little bit of maintenance to keep it in top shape. There are many parts to a treadmill, but the most obvious one is the running belt, also known as the walking belt, track, or treadmill belt. 

Knowing how to adjust a treadmill belt keeps it at the right tension and aligned in the center so you can safely exercise (and extend the life of your machine). This process is generally the same in most treadmill models, but we recommend checking your owner’s manual before taking any of the following steps. 

Signs You Need to Adjust Your Treadmill Running Belt

No matter the thickness of the belt, you will likely have to do a treadmill belt alignment at some point. 

There are a few signs you may need to adjust your running belt. The most common sign is when the belt shifts to one side. Your treadmill belt may be slowly drifting too far to the right or left, and this can cause the belt to stretch unevenly or fray. You might also notice that the belt feels like it’s stalling or having trouble turning over. It may also feel like it’s slipping or skipping under your feet.

The good news is this is one of the easiest parts of treadmill maintenance

woman adjusting nordictrack treadmill belt

Reasons Your Belt Tension May Need Adjusting

Over time, rubber stretches out and may become too loose. This is the most common reason you may need to adjust belt tension. A loose belt can become unstable and skip due to lack of tension. This can be a dangerous tripping hazard and it may cause the treadmill to stop working completely if not fixed. 

If you aren’t sure whether you need to adjust your treadmill belt tension, see how far you can lift your walking belt from the treadmill deck. If you can lift it more than 4 inches, you will need to adjust your belt tension before using it again. 

Another sign you may need to adjust belt tension is that the belt is slipping or skipping randomly. In most cases, applying lubrication and tightening the belt should resolve the issue. 

If you adjust the tension on the rear roller bolts and the belt is still skipping, then the issue may not be tension-related. Check to see if the drive belt may be loose. The drive belt connects the motor to the front roller and propels the belt. If the drive belt is loose, it causes the front roller to speed up and slow down sporadically making the belt “skip.” Refer to your user manual on how to tighten the drive belt or check if this is covered in your warranty. 

4 Steps to Tighten Your Treadmill Belt

If your treadmill walking belt is too loose, tighten it using the following steps: 

Step 1: Turn off the treadmill and disconnect it from the power source for your safety.

Step 2: Locate the adjustment bolts at the rear of the treadmill by the end cap.

Step 3: Tighten the treadmill belt. Most treadmill manufacturers use an adjustment point that requires either a hex key or Allen wrench. Turn the left and the right bolt one-quarter turn at a time to the right. Alternate between the left and right bolts to make sure they are adjusted in sync. 

Step 4: Place your hand under the belt and lift up. Prevent over-tightening, which could cause other issues. You have reached the proper tension when the belt lifts about 3 to 4 inches up from the running deck. Apply lube if you have not done so recently.

woman using tool to adjust NordicTrack treadmill belt

4 Steps to Loosen Your Treadmill Belt

If your treadmill belt is too tight, you may be experiencing slipping, which can cause you to trip and pose other treadmill safety hazards. You should be able to lift the belt 3 to 4 inches off the platform. If you cannot fit your hand under the belt or it lifts less than 3 inches, follow these steps. 

Step 1: Turn off the treadmill and disconnect it from the power source for your safety.

Step 2: Locate the roller adjustment bolts at the rear of the treadmill by the running boards.

Step 3: Loosen the treadmill belt. Using your wrench, turn the left and the right bolt in one-quarter increments to the left. Make sure you turn the left and right one after the other so they are adjusted in sync. 

Step 4: Keep turning the bolts until you can place your hand under the belt and lift up. If it lifts about 3 to 4 inches up from the deck, it is tight enough. 

4 Steps to Align Your Treadmill Belt

Sometimes the running belt can shift left or right. If this happens for too long, it can cause the belt to stretch unevenly or rub against one side and tear causing permanent damage. To avoid this follow these steps for simple belt adjustment. 

Step 1: Turn off the treadmill and disconnect the power cord for your safety.

Step 2: Assess which way the belt has shifted on the treadmill platform. You will be working the side the belt has shifted towards

Step 3: Locate the bolts at the rear of the treadmill by the running boards. If the belt has moved to the left, then you will locate the bolt on the left side and turn it in quarter turns to the right

If the belt has moved to the right, then you will locate the bolt on the right side and turn it in quarter turns to the right

Manually push the belt, let it rotate a few turns and watch the belt slowly shift. Keep turning the bolts in quarter turns and rotating the belt until it is back to the center. 

woman assessing nordictrack treadmill belt

Step 4: Plug the treadmill back in, turn the speed to about 3 MPH and make sure the belt stays centered and everything is running properly. 

Final Thoughts

All fitness equipment comes with some at-home maintenance. The good news is treadmills have some easy quick-fix options if they are not performing right. When in doubt, consult your user manual.

How to Adjust a Treadmill Belt FAQs

How do you align a treadmill belt?

To align a treadmill belt, determine which side the belt has shifted to and locate that tension bolt on the rear end of the treadmill. Turn the treadmill on to 3 MPH and allow a few rotations. Using a hex or Allen wrench, turn the bolt a quarter turn to the right. Wait a few rotations for the belt to move. Continue in quarter turns until the belt is centered. 

How do I adjust the tension on my treadmill belt?

To adjust the tension on your treadmill belt, locate the bolts near the rear of the treadmill. To add tension, use a wrench and turn both bolts one quarter turn to the right (clockwise). To loosen the belt, turn both bolts one quarter turn to the left (counter clockwise). Check the belt, continue to turn bolts a quarter at a time until you can fit your hand snugly between the belt and treadmill deck. 

Why does my treadmill belt keep moving to one side?

Your treadmill belt may shift from one side to the other over time. This can happen naturally over time as you use your machine. If your treadmill belt keeps moving to one side, it is most likely due to an imbalance of tension. To fix this, determine which side the belt slips to. Locate the rear bolt on that side. Turn the machine on to 3 MPH and using the proper wrench rotate the bolt in quarter turns to the right until the belt re-centers. 

How do you tell if your treadmill belt is too loose or too tight?

Slide your hand between the treadmill belt and deck at the center. If you can lift the belt from the center more than 3 to 4 inches, it is too loose. If you cannot lift the belt more than 3 inches, it is too tight. You should adjust the belt accordingly. 

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