Dishwasher Making a Grinding Noise: Causes & Fixes
Quick answer
A grinding noise in your dishwasher is often caused by a worn motor, trapped debris, or a faulty pump. Check for foreign objects, clean the pump, and replace parts if needed.
Confirm the symptom
- Hearing a grinding or rumbling noise during operation
- Noise occurs during the wash or drain cycle
- Sound is louder when the dishwasher is running
Tools and prep
- Screwdriver — For removing panels and accessing internal parts
- Flashlight — To inspect hard-to-see areas inside the dishwasher
- Plastic putty knife — To remove debris from the pump and drain area
- Socket wrench set — For tightening or removing motor components
- Work gloves — To protect hands during inspection and cleaning
Disclosure: We may earn a commission from qualifying purchases via affiliate links. Learn more.
Prep & safety
- Unplug the dishwasher to avoid electrical hazards.
- Allow the dishwasher to cool completely before inspection.
Step-by-step troubleshooting
Check for Foreign Objects
Do: Open the dishwasher and inspect the bottom for any trapped items like bones, pits, or small objects.
Observe: Find and remove any foreign objects that may be caught in the pump or drain area.
Means: Objects can damage the pump and cause grinding noises.
Next: If objects are found, clean the area and test the dishwasher.
Inspect the Pump and Motor
Do: Remove the lower panel to access the pump and motor. Use a flashlight to look for debris or damage.
Observe: Look for signs of wear, corrosion, or loose parts in the pump assembly.
Means: A damaged pump or motor can cause grinding sounds.
Next: If debris is found, clean it out. If parts are damaged, consider replacement.
Test the Motor
Do: Plug in the dishwasher and run a short cycle to listen for the grinding noise.
Observe: Note if the noise persists after cleaning the pump and removing debris.
Means: A persistent grinding noise may indicate a faulty motor.
Next: If the noise continues, the motor may need to be replaced.
Check the Motor Bearings
Do: Use a screwdriver to carefully inspect the motor bearings for wear or damage.
Observe: Look for signs of wear, such as pitting or rough surfaces on the bearings.
Means: Worn bearings can cause the motor to make grinding noises.
Next: If bearings are damaged, the motor assembly may need to be replaced.
Inspect the Drive Belt
Do: Check the drive belt for signs of wear, cracking, or looseness.
Observe: A loose or worn belt can cause the motor to work harder and produce noise.
Means: A faulty drive belt can lead to grinding sounds during operation.
Next: Replace the drive belt if it is damaged or worn.
Test the Dishwasher
Do: Run a test cycle after cleaning and inspecting all components.
Observe: Listen for any remaining grinding noises during the cycle.
Means: This confirms whether the issue has been resolved.
Next: If the noise is gone, the problem is fixed. If not, further inspection may be needed.
Common causes table
| Cause | Why | Likelihood | Difficulty | Part often needed |
|---|---|---|---|---|
| Trapped Debris | Foreign objects in the pump can cause grinding noises. | High | Low | No |
| Worn Motor Bearings | Worn bearings can cause the motor to make grinding sounds. | Medium | Medium | Yes |
| Faulty Pump | A damaged or worn pump can produce grinding noises. | Medium | Medium | Yes |
| Loose or Worn Drive Belt | A loose belt can cause the motor to work harder and produce noise. | Low | Low | Yes |
| Faulty Motor | A damaged motor can cause grinding sounds during operation. | Medium | High | Yes |
| Clogged Drain Hose | A clogged drain hose can cause the pump to work harder and make noise. | Low | Low | No |
| Improper Installation | Incorrect installation can cause parts to rub or bind, leading to noise. | Low | Medium | No |
| Worn or Damaged Impeller | The impeller can wear out or become damaged, causing grinding noises. | Medium | Medium | Yes |
Parts matching
When replacing parts, ensure compatibility with your dishwasher model.
- Pump assembly: match the model number and specifications from your dishwasher's manual
- Motor: check the voltage and amperage requirements
- Drive belt: measure the length and width to ensure a proper fit
- Impeller: verify the size and thread type to match the existing part
Consult your dishwasher's manual for specific part numbers and installation instructions.
Disclosure: We may earn a commission from qualifying purchases via affiliate links. Learn more.
When to call a pro
- The grinding noise persists after cleaning and inspecting the pump and motor
- You notice a burning smell or smoke coming from the dishwasher
- The dishwasher does not start or stops mid-cycle
- You are unsure about the cause of the noise or how to replace parts
- The dishwasher is under warranty and you do not want to risk voiding it
FAQ
Can I use the dishwasher while it's making a grinding noise?
It's not recommended to use the dishwasher while it's making a grinding noise as it may cause further damage.
How often should I clean the dishwasher pump?
Clean the pump and drain area every 3–6 months to prevent debris buildup.
Is a grinding noise always a sign of a serious problem?
Not always; it can sometimes be caused by a small object trapped in the pump, which can be easily removed.
Can I replace the motor myself?
Replacing the motor requires some technical skill and knowledge. If you're unsure, it's best to call a professional.