Product review (5 stars): This solved my issue for my Whirpool duet!!  Praise the heavens!
This fixed my issue.  My Whirlpool Duet Steam washer would give me a SUD error and eventually fall into a F35 error.  Online research had me try to run a Diagnostic of which did not get past the first step.  I cleaned the drain underneath the drum to no avail.  Everything was pointing to this piece since it would sometimes work.  I figured if it was a blockage of sorts, it would be more constant.  Got washer and dryer for 700 total.  I put this $92 part in it and I now have a great Washer and Dryer!  I would recommend getting the Washer Fan ( http://washer-fan.myshopify.com/products/breeze ) to control the humidity in the washer between loads.  And leave the door open when not in use!