I have a Maytag MDBH945AWS dishwasher that makes loud noises when running through the wash cycle. When first purchased the DW was whisper quiet. At about 6 months it was noticeably louder. Then just recently it alternates between clicking (sounds like the soft food disposer), loud vibrating hum, and the medium loud hum that has been steadily increasing. I've disassembled it down to the motor and haven't found the problem. No obvious abrasion from parts interference. Nothing in the pump assy.. Motor turns freely and almost noiselessly with no play up or down or side to side in the shaft. Impeller not chipped or damaged in any way. I'm stumped, PLEASE help.

SOURCE: Diswasher motor making noise during wash cycle

It could be the impeller on the motor. The impeller fits over the shaft of the motor and might have split/broken up. That funny noise is probably the shaft spinning inside the damage impeller. Fortunately the impeler is fairly inexpensive and easy to replace. I believe there are one or two parts/covers to remove that are held in by a roughly half dozen torx screws.

SOURCE: maytag dishwasher mdb56000aww

It seems that your motor on the dishwasher is going out, like mine has just done. My explanation is that it sounds like something is grinding on glass or as if a bunch of mice are making noise. Eventually, the motor will not run any more. What will happen is that the dishwasher will fill up, then make a loud humming noise, while the heating element is making the water near the heating element sizzle. Now what you have is a possible fire hazard which compounds the problem with the dishwasher. Get rid of it, take the loss and live like my grandmother used to, without having a dishwasher. That is the best advice I can give you.

SOURCE: Pump impeller rubbing on tub

Did or could have something get dropped on impeller?
Or a utensil get in it?
The metal shaft may have gotten bent or tweaked.
To adjust turn impeller till you see the rub.
Lift up side that is rubbing and down a little on the side that is not. Be very careful you are working with plastic.
Don't break it just a little at a time. Turn and check as you go.

SOURCE: Maytag dishwasher legacy 300 quiet series

I was so impressed with the advice on this website, I thought I would take a stab at this. The difference is, I will include all the steps, so if I go into a little too much detail for you, I'm sorry, but I felt a few things got left out that needed to be said.

Tools Needed: screwdriver with t-15, and t-20 torx bits (available at any hardware store), and a pair of pliers. Also I used a headlamp so I did'nt have to hold a flashlight with my teeth.

step#1- Clear a spot on your counter or kitchen table and remove both the lower and upper racks from your dishwasher. The lower rack just lifts out, the upper you will find two light blue plastic caps that once removed will allow you to slide the rack off of the metal slides. Next, the long L shaped spray bar that goes up the back and across the top needs to be un-clipped and removed, 2 clips at top and 2 clips at the back. It might take a little wiggling but that spray bar slides into the top cover, once unclipped push back at the bottom and tilt the upper part toward you, it should come out fairly easily and give you wide open access to the cover. Next you want to remove the plastic nut that holds the spinner in place, using your pliers turn it counter clockwise, it should loosen fairly easily, and remove nut and spinner. Next with either a T-20 or T-25 torx bit, remove the 3 screws that hold the outer cover in place, notice the direction of the tube that plugs into the spray bar, make sure it goes back in the same way. Now remove the T-15 screw that holds the black grinder cover in place and remove screw and cover. Now remove the 6 screws that hold the inner cover in place and remove the cover. You can now see what all the fuss was about, mine included a piece of pistachio shell, a bay leaf, and a cherry pit. Once it's all cleaned out, just reverse these steps and be ready! You have just earned your place as your homes resident handyman or woman!