What would cause your black tank valve to work open when traveling?

[WhittleBurner]

Those cables on the gate valves are pretty easy to cut and adjust the length of them so they would operate easier. On those high price motor homes they would have more time to make these adjustments and routing with ties to hold them in place.If you have to drop your choroplast it would not be too hard for someone to do.

[almo88320]

I do this too as mentioned in my note above. It doesn't do the trick. What I haven't tried is tipping the trailer side-to-side with the levelers, but I'd guess that's a pretty hairy thing to do and it would only prove what I already know: that the drain plumbing was badly-designed and/or badly installed by Grand Design.

Same with my 2018 GD 250RL ... it is annoying as all get-out, I had the same experience with my GD dealer, they wanted me to deal with the toilet paper they said causes "knife valve" to not fully shut (leaks a lovely ooze!) and the handle seems to have a good bit of corrosion. Simply put, the valve handle doesn't seem to close as fully as it used to. Would GD cover this under the extended warranty? I agree it is poorly engineered, especially if the valve handles experience corrosion after 12-18 months of limited use. I feel sure it is this, not gravity as some on this thread have stated, causing the issue.

[Carolina]

My friend used the same thing and he had no fewer problems. He was furious when he calmed down he went to another service and completely changed. All I know is not the best choice