With Samsung's website being USELESS, researched on YouTube. Live chat on Appliance Pros came up with the part for the DMT800RHS which fits the 400 - this was the easiest site to research and Samantha was great in getting the order in for overnight delivery. Decided to replace for ~$100 rather than spend ages washing part out. Removing/replacing the electrical wiring was the most awkward of the tasks. Pulled the machine 3/4 of the way out. Rotate & remove the filler inside the washer, disconnect 4x hoses (long nose pliers to remove/replace clips) suggest marking L & R. A little soapy water to ease the hoses back on. 3x electrical connectors (small screwdriver to release the connection) each are unique so no confusion. Just make sure to locate the two pegs at the bottom as you are re-positioning. Watch the videos and you are set for an easy replacement.