Product review (5 stars): fixed leaking duet sport washer
Perfect replacement for whirlpool duet sport washer model WFW8300SW03.

I verified the part number, and it was a higher revision than mine, but otherwise was an exact match.

The part number printed on the new bellows was 8540952/12, mine was 8540952/5.

I had to trim the openings on the drain port a little bit, as they were not cut perfectly and there was some excess material.  Otherwise, no worries.

Note that this part is delivered by different suppliers, so your mileage may very based on the supplier.  The one I got was delivered by Primeco.

The hardest part of the repair was to get the outside bellows spring-clamp back in place.  Easy to remove, hard to put back!

I recommend youtube video NTSiin55Ynk.  The fellow in this video was very thorough, even if the camera work was spotty at times.

Don't forget to clean out the drain filter, which is visible when you remove the bottom panel.  Mine was really gross, since I didn't even know about it in the 10 years we have owned this washer.  It needs to be cleaned regularly.  I believe it was the main reason that the washer was extending the time of the cycle, because the clogging made it drain more slowly.

On the bright side, I found 87 cents in there.

Also, run the clean cycle with some bleach only - it is how I verified the leaking door, and removed soap residue that had built up over the years.