Whirlpool documents Sud or Sd as excess suds that can keep the washer from spinning out water and may extend rinsing.
Front Load Washer; United States. This page is not a brand-wide diagnosis.
The washer may display Sud or Sd, pause tumbling, add water for extra rinses, take longer than expected, or struggle to spin out water.
Stop using the washer if suds overflow, water leaks, the drain path is unsafe, or the washer remains full of water.
Record detergent type, detergent amount, bleach type if used, drain hose routing, and whether Sud or Sd returns on normal loads.
This symptom page is attached to Front Load Washer. It is not a brand-wide diagnosis.
For Whirlpool front-load washers, Sud or Sd is documented as excess suds; the article also connects this condition with HE detergent use and possible drain hose or standpipe restrictions.