If you think there is build up in the gray tank, you might try treating it with black tank chemical and flush out as you would the black tank. If it is still construction debris that is floating and then plugging the outlet as it drains, my dealer's service department stated that the tank would have to be removed and cleaned out, I decided to live with it for the present time hoping things dissolve some and flush out. If it is a sensor I will also live with it for the time being.
clparalegal, thanks for the pm Thank You.
2006 Silverado 2500HD Duramax
2010 Prime Time Lacrosse 303RKS
2007 Hensley Arrow Hitch
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