Here is a question regarding the check valve in the drain hose for this model. Is the check valve supposed to stop 100% of the water from flowing back into the washer? Since we had ours apart for another reason, we decided to clean out the drain hose (we have well water and sometimes there is sediment etc.) so, we noticed that the check valve seemed to let a continuous small trickle of water pass back through it when under a full column of water. Not sure if it supposed to or not. If not, we will replace it while we have the thing apart. If a small amount of water passing back through the check valve is what it is supposed to do, then we will put it back. It would seem reasonable that water flowing back into the tub would cause a mold/smell issue.

We tried rinsing bleach through the hose for a considerable amount of time with no change (in case a piece of junk was holding the check valve open). Does anyone know if this is a ball or flap type valve?:confused:

Eschutt, Your term " flow limiting valve" is a better description than a "check valve", No the valves will not be 100 % sealed, 95 to 99 % is more realistic.
Did you also check the "check valve" in the drain pump [AP4359940] on the outlet portion of the drain pump ? As long as the drain hose is installed and allowed to "hang" properly in the drain stand pipe, there will be no issues, if you have taped or sealed the hose to the pipe, then there may be.

You need to remember, water seeks it's own level, and there is always water remaining in the hoses and drain pump, this acts as a seal to eliminate odors from the drain system and "stack gas" from developing in the washer tub. Just like the "P" trap in the sinks in your home.

"contributing to the problem that many front load washers have - smelly laundry syndrome"

Smelly Laundry syndrome is not due to the washer or the drain system, unless the issue is obvious, (inoperable drain pump, kinked hoses, sealed drain hose, etc.) The majority of odor issues in front load washers are due to mis use: overloading, improper amount and type of detergent and additives, and cold water washes. You need to remember, these style washers operate on 5 to 7 gallons of water per fill, you shouldn't load the tub more than 2/3 to 3/4 full with dry clothes, use the proper amount and type of detergent for the soil level and type of articles being washed. and use the hottest or warmest water temperature setting for the articles washed. This will help to resolve the odor issues. You may have to remember to leave the washer door open when not in use, and run a "clean" cycle with a product like "Affresh" occasionally. But you should see a reduction in the odor and eventually the odor will dissipate and become non existent.