That does sound like a plugged vent. Glenn is possibly correct on this. The other possibility is you are getting a pyramid buildup of paper, if you're not putting enough water down the drain when you flush. Been there. It's not fun. If you think this might be a problem then trip on down to your RV dealer and buy some tissue digester. Follow the directions precisely. It works. I tried all the other solutions suggested, like put ice cubes in there and take a drive, etc. Once it gets that bad, only the tissue digester worked for me. Yours may well be the vent, though.
Did you run the snake down the vent from the roof?
See another Montana or Mountaineer on the road? Flash lights twice, it might be one of us!
Steve Reigle (pronounced Regal)
Fulltiming since 3/21/03
'03 3295RK
'05 Ford F250 SD Lariat CC SB 6.0L PSD/TS FX4 4x4
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