Shower drains to black tank on 2020 328G

[ncitro]

Jasondennis Hi Jason I edited your post to remove your phone number. We get a lot of probes here from unwanted phishing attempts, and it's not a good idea to post it. I see this is your first post, welcome and feel free to check out our welcome letter to new members:

https://gdrvowners.com/forum/main-fo...to-new-members

This post is quite old, and the most recent user did not ever update us with their resolution, but I'd suggest starting with a call to customer service. Even out of warranty they may still work with you for a good resolution.

If you're looking to take this on yourself you've come to the right place,but I don't think this will be for the faint of heart, especially with a few years of use in the black tank. I'd think the first step would be to drop your coroplast underneath the rig and get eyes on the situation to see where your plumbing is routed and where your tanks are located.

[Cate&Rob]

Jasondennis

This is a “take it apart and put it back together correctly” situation. The question is, who will do this? You should certainly contact Grand Design because it does not seem that this was put together correctly in the first place. If they agree and if you can get the trailer to their factory repair center in Indiana, that would be the ideal solution. It is possible that they would authorize a dealer to sort this out . . . but, that could be a long wait. You could hire a service tech to resolve this. You could tackle this problem yourself if you feel capable of doing this. The drain system on an RV is basically the same glued together ABS components found in residential plumbing. Most of what you will need can be found a Home Depot or similar.

Rob

[707electrician]

Found this thread after doing a Google search on this very issue. Bought our 2020 328G used about a month ago and took it out for our first trip this past weekend and was shocked when my black tank was full after only 2 days of just myself using it. I figured the only explanation was that the shower and toilet were both plumbed to the black tank but this means that just the bathroom sink is running to the front grey tank. I thought this was a pretty stupid design, but now after finding this thread I realize that this likely isn't by design. My number one concern with buying a newer rig was getting something with covid era quality control, and unfortunately we don't have a warranty to take care of this issue. Pretty sad that a trailer that probably cost nearly $100k when it was new would make it out the door like this and even worse that it is seemingly a common issue.

[howson]

Found this thread after doing a Google search on this very issue. Bought our 2020 328G used about a month ago and took it out for our first trip this past weekend and was shocked when my black tank was full after only 2 days of just myself using it. I figured the only explanation was that the shower and toilet were both plumbed to the black tank but this means that just the bathroom sink is running to the front grey tank. I thought this was a pretty stupid design, but now after finding this thread I realize that this likely isn't by design. My number one concern with buying a newer rig was getting something with covid era quality control, and unfortunately we don't have a warranty to take care of this issue. Pretty sad that a trailer that probably cost nearly $100k when it was new would make it out the door like this and even worse that it is seemingly a common issue.

Consider contacting GD Customer Service. Explain the issue. No guarantee, but it won't cost anything to call except a few minutes of your time.

Phone number on home page of this forum.

If you haven't seen it, there's a thread on how to inform GD of an ownership change (if they do not know already): https://gdrvowners.com/forum/main-fo...of-a-used-unit

Also--welcome to the forum! Please check out the Welcome Letter: https://gdrvowners.com/forum/main-fo...to-new-members

Howard