When your handy-dandy dishwasher starts to make unnatural noises, it can be really troubling. Especially if you are someone that uses your dishwasher every day. Here are some of the most common noises that can happen and how to troubleshoot the problem and determine if it is time for dishwasher repair.


At certain times, it is normal for a dishwasher to make a humming noise. When a humming noise happens at an unnatural time or if the noise is getting louder, it could be the result of a faulty fan or a malfunctioning motor. These parts can be purchased and replaced fairly easily. Don’t forget to cut the power to the machine while troubleshooting and when replacing or repairing parts.


This noise can naturally happen when the machine is draining water or when the food disposal unit within the machine is doing its’ job. When this sound gets louder or even sounds more like a banging, it can be contributed to a problem known as a water hammer problem. Rapid jets of water being forced through various pipes can cause the pipes to bang on things that are around it.


If your dishwasher has a motor-driven electrical switching device that is run by an electronic control, a grinding noise can be a normal sound to hear. As the machine switches through cycles, the motor will make this noise as it works.

If this sound happens at an unnatural time, it can be because of one of two reasons. One may be that there are some things in the bottom of the dishwasher that are impeding the drain propeller (the rotating plastic blades at the bottom of the machine). You can check this by stopping the machine mid-cycle and checking for anything in the bottom that would impede the propeller. If there is nothing that is doing this, you may need to take the impeller out and check for something in the chopper blade area of the dishwasher.

The other reason that this may happen is that there is not enough water getting into the machine during the cycle. This is when you will want to check the water inlet valve of the machine.


There are instructions that are given to owners as to how the dishes need to be loaded into the dishwasher for a reason. If the dishes are not loaded properly, they can be rattling and clanging around and banging into each other. Try to reorganize the dishes to see if the noise stops. If not, it could be a result of a motor problem.

It is easy to troubleshoot by simply running the machine when it is empty. If the noise happens when the machine is empty, it is due to a problem with the dishwasher motor.


The spray arm inside the dishwasher rotates around in order to clean the dishes properly. A knocking noise may indicate that there is something that this arm is hitting as it rotates. You may just need to adjust something inside the machine that is getting in the way of this spray arm.


It is quite normal for brand new machines to make a squealing noise for the first few times that they are used. Once they are used a few times and there is water throughout the machine, this noise should go away. Also, it is common for this to happen if you are not regularly using your dishwasher. Add a quart of water to the bottom of the machine in order to reduce this squealing sound.


A thumping noise is likely going to be a result of something hitting on something else. It could be a result of the spray arm knocking into something as it rotates. This can be resolved with a simple adjustment of the pots, pans, or whatever is located in the bottom of the machine.

If the machine is newly installed, it can be a drain line that is hitting the cabinets or the wall at the back of the machine. This can be resolved with a simple readjustment of this line so that it doesn’t hit on anything as water is drained out.


This is quite a common noise to hear. There is a solenoid that charges every time that the machine drains and fills and this charging will produce a snapping noise. The door can also make this noise if the model has a hinged detergent cup that needs to be pushed closed. There can be a problem with the door hinges if you do not have a “turn-to-close” model.