Why Is My Dishwasher Making A Grinding Noise?

You’ve just finished cleaning up after a nice meal, and you’re settling in for some hard-earned Netflix time when you realize: Your dishwasher is making a weird noise, and you can hear it from the couch. Dishwashers have many parts, but with a little know-how, you can troubleshoot and fix this annoying issue. Here are seven reasons why your dishwasher is making a grinding noise and what you can do about it.

1. Clogged Spray Arms 

Dishwashers use spray arms to clean the dishes, and sometimes these arms become clogged with flyaway food particles or hard water buildup. 

How to Fix It

To clean the spray arms, use a wire or toothpick to push debris free of the holes. Rinsing your dishwasher with vinegar or investing in a water purification system can prevent the spray arms from building up with hard water buildup. 

2. Blocked Pump

At times, small utensils or food pieces may become stuck in the pump or chopper blade, causing a loud grinding sound. 

How to Fix It

Examine the bottom of your dishwasher for any items that don’t belong there and remove them cautiously.

3. Plugged Inlet Valve

Another place where your dishwasher can get clogged and cause a grinding sound is in the inlet valve. Homes with hard water are especially susceptible to limescale buildup that can plug the valve and make it difficult for water to flow through the appliance. 

How to Fix It

Unclog the inlet valve by disconnecting the hose, cleaning the sediment filter if you have one, and brushing away debris and sediment.

4. Blocked Chopper Blade

The chopper blade rotates at the bottom of your dishwasher to break up food and prevent clogs in the drain. If the blade can’t operate due to a clog, a piece of cutlery, or broken debris, it can cause the machine to grind. 

How to Fix It

Remove debris from the chopper blade to see if that fixes the issue before replacing the part.

5. Faulty Motor Bearings

If water gets into the motor bearing of your dishwasher, it can corrode the metal and cause a grinding sound. Keep in mind that not all dishwasher types have motors that require lubrication, as many have sealed bearings to prevent water damage. 

How to Fix It

To prevent corroded motor bearings, regularly lubricate your dishwasher according to the manufacturer's instructions. If your motor bearings are badly rusted, you may need to replace them.

6. Worn-Out Pump Assembly

Part of your dishwasher contains two pumps: a drain pump and a circulation pump. If either one of these pump assemblies gets worn out or clogged, it can cause grinding noises. 

How to Fix It

Check for debris and clean the pump to see if that fixes the problem. If you notice wear and tear, you’ll need to replace the pump. 

7. Loose Dishes

Grinding from loose dishes can also cause your dishwasher to make a loud noise. Fortunately, this is an easy-to-fix user error.

How to Fix It

The best way to fix this problem is by properly filling your dishwasher (consult your manual for tips) and looking for loose dishes at the bottom.

When to Call a Pro

After investigating and trying out these DIY solutions, you may need to hire a local dishwasher repair pro to troubleshoot or replace the dishwasher if your unit continues to make grinding noises. The average dishwasher installation costs $1,000 to $1,500, depending on the type of dishwasher and ease of access. 

How to Prevent Your Dishwasher from Making a Grinding Noise

Prevention measures can go a long way in extending your dishwasher’s life, saving you on repair costs and the stress of having lackluster, partially cleaned dishes. Here are some ways to maintain your dishwasher and keep issues from arising prematurely:

• Routinely clean your dishwasher using white vinegar to help loosen clogs and keep them away.

• Sprinkle baking soda at the bottom of the dishwasher and run a quick cycle. 

• If your dishwasher shares the same plumbing as your garbage disposal, clean the garbage disposal simultaneously to keep the whole plumbing unit clean. 

• Replace broken parts as soon as you notice them.

• Regularly inspect and clean the filter.

• Load dishes according to the instructions for your dishwasher brand.

• Avoid overloading your dishwasher.

• Use the correct dishwasher detergent—and the right amount.

• Regularly use your dishwasher to keep buildup from collecting.