KitchenAid's manual for the KDTM604KPS gives a two-line fix for thumping and clattering: load dishes so they do not touch one another, and make sure lightweight items are secured in the racks. Its help article adds the normal sounds: rushing water while it fills and cleans (louder for a dishwasher at the end of a cabinet row), a hum when the drain pump runs and swishing as the spray arms turn. The ProScrub jets and Bottle Wash nozzles are additional spray components on this model, so a different-sounding wash phase can just be an option running.
Differential
Likely causes of “KitchenAid dishwasher makes grinding, humming, knocking or squealing noises”, and how to tell them apart
- 1
Dishes touching or lightweight items loose
What separates it A rhythmic clatter as the arms sweep across loose plastics and lids
How to confirm Load dishes apart and secure lightweight items; the manual says this avoids thumping
- 2
Normal fill, wash and drain sounds
What separates it Rushing at fill, swishing in wash and a hum at drain
How to confirm Compare with the article's list; these are normal
- 3
A spray arm blocked by an item
What separates it There is a knock each time the arm turns because a spray arm is blocked by an item
How to confirm Check items in the rack do not block the upper or lower spray arms
- 4
An unlevel or loosely mounted dishwasher
What separates it There is vibration carried into the cabinets because the dishwasher is unlevel or loosely mounted
How to confirm Check the leveling legs, mounting brackets, insulation and toe kick
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which phase the noise happens in
- Whether it stops when the racks are empty
- Whether the dishwasher sits at the end of a cabinet run
Try in this order
0 of 5 completedLoad so dishes do not touch
ReversibleThe manual says to load dishes so they do not touch one another and to make sure lightweight items are secured in the racks to avoid thumping or clattering.
Check the spray arms
ReversibleBe sure items in the rack do not block the upper or lower spray arms; turn the arms by hand to check they move freely.
Match the sound to the phase
ReversibleRushing water, a hum from the drain pump and swishing are normal, and the amount depends on the installation.
Check level and mounting
ReversibleVerify the leveling legs, mounting brackets, insulation and toe kick panel are correctly fitted so vibration does not reach the cabinets.
Clean the filters
ReversibleClean the filters, since routine cleaning of the filter and spray arms keeps the normal sounds normal.
Model-specific
What is true of this model and not of its siblings
- ProScrub and Bottle Wash
- ProScrub uses lower jets spraying from behind the lower rack and two spray zones in the front corners of the upper rack to reach deeper items, and Bottle Wash adds six retractable nozzles in the upper rack that flip up to use and down to move out of the way. They are on some models and add their own spray noise.
- Controls, delay and control lock
- Delay runs the dishwasher later or in off-peak hours: pick a cycle and options, press Delay, press START/RESUME and close the door firmly, and note the countdown needs START/RESUME pressed again any time the door is opened. Control Lock is turned on or off by holding the model's lock button for 3 seconds; the door still opens while locked, and pressing a button flashes the light three times. If the door is opened or power is interrupted the Start/Resume light flashes, and the door must be pushed firmly closed within 3 seconds of pressing Start/Resume.
- Parts for this problem on the KDTM604 (RepairClinic, 2026-09-21)
- circulation pump & motor assembly, part number W11414076, at $200.31; drain pump, part number W11412291, at $85.55.
- Other models this page answers
- These steps also fit the KDTM804 dishwasher, KDTE204 dishwasher, KDTE304 dishwasher, KDFM404 dishwasher.
Stop boundary
When this stops being a self-service repair
- !If scraping or grinding continues with empty racks, stop and contact KitchenAid service
- !If noise comes with a leak or a flashing light, use those pages first
Evidence ledger
Sources behind this answer
KitchenAid's own manual for this model, English pages 1 to 8: operating, cycle guide, options, care and the Problem Solver table.
KitchenAid's own help articles for its dishwashers, each; the article for this page is named in the page's notes.
KitchenAid's own help articles on drying, cleaning, spotting, cycle length, sounds and interior cleaning.
KitchenAid's own page for this model's manuals and support.
Parts and list prices as shown on RepairClinic's parts search for this model number on 2026-09-21.
Exact questions
Common questions
What causes clattering?+
Dishes touching each other or lightweight items that are not secured.
Is humming normal?+
Yes. It is the drain pump running.
Why does it sound like rushing water?+
That is normal during fill and clean, and is louder at the end of a cabinet row.
Can a blocked arm cause noise?+
Yes. Items that block a spray arm knock against it.
Do the ProScrub jets sound different?+
They spray from behind the lower rack and the upper rack corners, so the wash phase can sound different.
Can the dishwasher be too loud to fix at home?+
Grinding or scraping needs service, since it can be too loud to fix at home.
Can I turn off the beeps?+
Hold Hi Temp Wash for 3 seconds; only the confirming tones can be silenced.
Does a full load reduce noise?+
Not by itself; overloading makes dishes touch and clatter.