Treadmill: Why does my treadmill's walking belt slow down?

A damaged walking belt, improper belt tension, lack of belt lubricant or a bad drive motor can cause the walking belt to slow down when you step on the belt.

Unplug the treadmill, then check the walking belt for damage and replace the belt if it's torn.

If the belt is in good condition, check belt tension by lifting the middle edge of each side of the belt. If the belt is properly tensioned, you should be able to lift the belt's edge up 2-3 inches above the walking board. Adjust belt tension if the belt is too loose or too tight.

If belt tension is okay, then you might need to add belt lubricant to the walking board so the belt slides easily across the board.

A weak drive motor can cause the belt to slow down when you step on the treadmill. If the belt is properly adjusted and lubricated, then you might need to replace the drive motor if the motor can't spin the roller to drive the belt at the set speed.

treadmill

These repairs may help solve your treadmill problem

Replace the treadmill walking belt

Replace the treadmill walking belt

The walking belt rotates rubs over the platform while walking which can wear and cause the walking belt to slow down when walking. Replace the walking belt when worn or damaged.

How to replace a treadmill walking belt

If your treadmill walking belt sticks, the belt could be worn. This repair guide and video show how to replace a treadmill walking belt with step-by-step instructions.

Repair difficulty
Time required
 45 minutes or less
Read more
Replace the treadmill motor

Replace the treadmill motor

The motor spins the front belt roller to rotate the walking belt. If the motor is weak or defective, replace the motor.

June 1, 2015
By Lyle Weischwill
How to replace a treadmill drive motor

If the treadmill won't start, the problem could be a worn motor. This repair guide and video show how to replace a treadmill drive motor in 6 quick steps.

Repair difficulty
Time required
 15 minutes or less
Read more

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

Main causes: faulty sensors, wiring failure, bad control console
Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor control board
Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor
Main causes: bad control console, wiring failure, bad motor control board
Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor
Main causes: damaged walking belt, improper belt tension, bad roller bearing
Main causes: rear roller out of alignment, damaged walking belt, bad roller

Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

June 1, 2015
By Lyle Weischwill
How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the motor correctly.

Repair difficulty
Time required
 15 minutes or less
How to replace a treadmill walking belt

A worn walking belt will begin to slow down during use. If your treadmill walking belt is worn out, replace it using these steps.

Repair difficulty
Time required
 45 minutes or less
June 1, 2015
By Lyle Weischwill
How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn't run.

Repair difficulty
Time required
 15 minutes or less

Articles and videos for treadmills

Use the advice and tips in these articles and videos to get the most out of your treadmill.

December 21, 2016

How to troubleshoot treadmill problems

By Sears PartsDirect staff

See what to check if you're having a problem with your treadmill, and what you can do to fix it.

May 10, 2015

How to maintain a treadmill

By Sears PartsDirect staff

Keep your treadmill in shape by following these tips.

January 1, 1970

How to tell if a fuse is blown

By Lyle Weischwill

Learn how to tell whether a fuse is blown