Steve, Larry Brandt posted (June 2012) about this subject.  Search our forums for 'frig seal"
".....  I ripped out my old refrigerator seal completely because it was getting 'gungy', and I installed a new seal. The new seal was simple weatherstripping I purchased from Home Depot. I found that what keeps the fridge doors from laying flat is the seal strip that fits between the two top halves, near the hinge. If that gets too 'fat', then the two doors will never be able to lay completely horizontal."