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Replacement parts for WHIRLPOOL KUDP01FLSS1 Dishwasher | AppliancePartsPros.com

A better description of the noise may help.
Remove the kick plate and try to answer the questions Where and When.
Are there any other symptoms re: poor washing or water left in the unit etc.

A symptom of just"an unusual noise" could be just about anything.

I am assuming that the noise is something new and it used to run quiet.

Sounds like you have checked out the main pump so all that is left is the drain pump.

Perhaps this will help
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/4e8b0d2df77cd7e585256cd800643b6d/$FILE/KD01.pdf

Also here is the tech sheet in case you do not have it
http://www.servicematters.com/docs/wiring/Tech%20Sheet%20-%208537797.pdf

Hopefully someone else will jump in who has seen this problem.

I have a new dimension to this problem....I have run the dishwasher a few times, although I noticed what appears to be a cavitation sound or loose bearing/shaft rubbing sound, I have also noticed what appears to be very fine metal filings on the horizontal flat surfaces on some of the glassware in the upper rack and also at the bottom of the stainless steel tub...is this a motor replacement at this point?

I was able to pull the drain pump and main pump last night...while pulling everything apart, I noticed the cutting blades on the chopper assembly were worn and I think that explains the metal fillings I have seen recently. Both pumps look fine, can't see anything obviously wrong. The main pump separation screen (part # 8268391) was at least 50% obstructed with crude and showed signed of wear and tear. I intend to replace that and the chopper assembly and see if that takes care of the overall problem. Any advice, while I have the two pumps out, on what I should be looking for that would indicate I need to replace them? The parts move freely and I see no damage, fluid leaking, or anything else that would lead me to believe they were damaged or getting ready to go. Should I be thinking of replacing anything else while I have everything apart...dishwasher is almost 7 years old....

Thanks for your previous advice...I finally got the parts I ordered and I put everything back together correctly it seemed until I turned on the washer. I had a significant water leak from what appeared like the left side of the sump seal. Do I need to apply any particular product (grease, lubricant) on the seal before re-attaching it to the sump and then seating on the stainless steel bottom? Any special technique for pushing in the sump tabs....I installed all three and I thought pushed them in as far as they would go in their recessed slots. Any other suggestions? I cleaned the pump seal after originally removing it earlier and didn't notice any holes or defects before putting it back into place. Again, thanks for any advice.

This has been bugging me all night. I am now thinking that the sump seal needed to be folded over into the sump housing??? Do I need to put anything between the seal and the stainless steel housing? Or, does the weight of the sump pump housing, motor, and everything else along with the sump tabs create a watertight seal? Thanks.