Is it possible to install bigger grey water tanks?

[Tony Ramage]

That’s incorrect. There’s only three tanks.

One grey tank for the shower, the bathroom sink and kitchen sink.
One black tank for the front toilet near the shower.
One combo grey/black for the rear half bath (if option selected) and washer dryer hookups.

Interesting. I called Grand Design and asked them about the grey capacity and if it is actually 78 gallons. He said that the grey tank capacity of 78 gallons was split into two separate tanks. One for main living area and one for the back half bath. So only 39 gallons each. But that doesn’t make sense to me as why they would have the same capacity in the main area, that gets used a lot, and the same in the half bath which rarely gets used. But what you said makes sense to me having the half bath combo of grey/black.
Thanks for the info.

-Tony

[alkbch]

@Tony Ramage; My understanding is Grand Design uses 52 gal tanks. In your model and mine, there are three tanks, 1 grey, 1 black and 1 combo (grey/black). Therefore, in the specs sheet, they split the combo tank capacity in two and add half to grey and half to black.
Which is why we see a capacity of 78 for grey and 78 for black. (52 + 52/2 = 78)

[Tony Ramage]

@Tony Ramage; My understanding is Grand Design uses 52 gal tanks. In your model and mine, there are three tanks, 1 grey, 1 black and 1 combo (grey/black). Therefore, in the specs sheet, they split the combo tank capacity in two and add half to grey and half to black.
Which is why we see a capacity of 78 for grey and 78 for black. (52 + 52/2 = 78)

@Tony Ramage; My understanding is Grand Design uses 52 gal tanks. In your model and mine, there are three tanks, 1 grey, 1 black and 1 combo (grey/black). Therefore, in the specs sheet, they split the combo tank capacity in two and add half to grey and half to black.
Which is why we see a capacity of 78 for grey and 78 for black. (52 + 52/2 = 78)

Oh, So really I have 52 gallons of black and 52 of grey for main area and 26 gallons of each in the combo?
Kind of a sneaky way to make it sound much better then it is.

[alkbch]

Yes that is my understanding, three 52 gal tanks for your model. It is actually less sneaky than before, because at least the total of grey + black is correct = 156gal.

If you look at the specs for the 395ms floorplan, they advertise 104 grey and 104 black whereas in reality it only has three tanks, and therefore the total grey + black capacity is the same as yours = 156gal. The reason they gave back then was that depending on use, you could get up to 104 grey or 104 black...

[Tony Ramage]

Yes that is my understanding, three 52 gal tanks for your model. It is actually less sneaky than before, because at least the total of grey + black is correct = 156gal.

If you look at the specs for the 395ms floorpan, they advertise 104 grey and 104 black whereas in reality it only has three tanks, and therefore the total grey + black capacity is the same as yours = 156gal. The reason they gave back then was that depending on use, you could get up to 104 grey or 104 black...

Ah, I see. Well thanks for clearing it up for me. Now I know to keep my eye on it closer when dry camping.
Thanks!

[Swbailey]

Y'all need to think more about your water use practices than trying to modify your rig.

Apologies if that sounds rude but this isn't your sticks and bricks home where you might let the water run continuously while you brush your teeth, shave or rinse dishes. Conservation and moderation. Spend less time dumping and more time doing fun things.

[huntindog]

Y'all need to think more about your water use practices than trying to modify your rig.

Apologies if that sounds rude but this isn't your sticks and bricks home where you might let the water run continuously while you brush your teeth, shave or rinse dishes. Conservation and moderation. Spend less time dumping and more time doing fun things.

You are being kind of harsh and for no reason.
If I do not like how something is working on my sticks & bricks, my RV, or my autos, and it is possible to make it more to my liking.... I do so. If you are content to work within the limitations of the things you own, I am happy for you.

Happy camping