Quick answer
Turn off the dishwasher and unplug it. Check for loose items or debris in the bottom. If the noise continues, inspect the pump, motor, or drain system for issues.
Confirm the symptom
- Unusual grinding, rattling, or whining sounds during cycles
- Noise occurs only during certain parts of the cycle
- You hear loud vibrations or knocking sounds
Tools and prep
- Screwdriver set
- Flashlight
- Work gloves
- Bucket
- Plumber's putty
- Turn off power at the circuit breaker
- Shut off water supply to the dishwasher
Step-by-step troubleshooting
- Turn Off Power and WaterDo: Shut off the circuit breaker for the dishwasher and turn off the water supply valve.Observe: Dishwasher stops running and water flow ceases.Means: Safe to proceed with inspection.Next: Check for loose items
- Check for Loose ItemsDo: Open the dishwasher and look for loose dishes, utensils, or foreign objects in the bottom.Observe: Find and remove any loose items.Means: Objects can cause rattling or knocking noises.Next: Inspect the pump and motor
- Inspect the Pump and MotorDo: Locate the pump and motor (usually at the bottom) and check for blockages or damage.Observe: Find debris, rust, or worn parts.Means: Blocked or damaged components can cause grinding or whining.Next: Test the drain system
- Test the Drain SystemDo: Check the drain hose and filter for clogs. Clean the filter if necessary.Observe: Clear any blockages in the drain hose and filter.Means: Clogged drains can cause unusual noises during draining.Next: Check the door seal
- Check the Door SealDo: Inspect the door gasket for damage or debris.Observe: Find cracks, tears, or trapped objects.Means: A damaged or dirty seal can cause vibrations or knocking.Next: Test the dishwasher
- Test the DishwasherDo: Plug the dishwasher back in, turn on the water and power, and run a test cycle.Observe: Listen for the same noises or any changes.Means: If the noise persists, further inspection or professional help may be needed.Next: End
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Loose or trapped objects Items in the bottom of the dishwasher can rattle or knock during operation. | Common | Easy | None |
| Clogged drain or filter Debris in the drain system can cause gurgling or loud noises during draining. | Common | Easy | Dishwasher filter |
| Worn pump or motor A damaged or worn pump/motor can cause grinding or whining sounds. | Sometimes | Medium | Pump or motor assembly |
| Faulty door seal A damaged or dirty door gasket can cause vibrations or knocking. | Sometimes | Easy | Door gasket |
| Loose internal components Loose parts like the spray arm or rack can cause rattling. | Sometimes | Easy | Spray arm or rack |
| Air trapped in the system Air bubbles in the water lines can cause knocking or hammering. | Rare | Easy | Plumber's putty or air bleed valve |
Parts matching
If you need to replace parts, here are common replacements for this issue:
- Dishwasher filter
- Pump or motor assembly
- Door gasket
- Spray arm or rack
- Drain hose
Check your dishwasher model number to ensure you get the correct replacement parts.
When to call a professional
- Noise persists after cleaning and checking all components
- You hear loud grinding or burning smells
- You suspect electrical issues or motor failure
- You're unsure about disassembling internal parts
- The dishwasher is under warranty and you don't want to risk voiding it
FAQ
Why does my dishwasher make noise only during the drain cycle?
This is often caused by a clogged drain filter or hose. Clean the filter and check for blockages in the drain system.
Can a noisy dishwasher damage other appliances?
Usually not, but loud vibrations can loosen connections over time. Address the issue promptly to prevent further problems.
Is it safe to use my dishwasher while it's making strange noises?
It's generally safe, but stop using it if you hear loud grinding, burning smells, or see sparks. These may indicate serious issues.
How can I prevent future noises in my dishwasher?
Regularly clean the filter, avoid overloading the dishwasher, and check for loose items before starting a cycle.