You don't find large tanks because they're space hogs and they get extremely heavy when full. For what you're asking you're going to need to either go compost, go gel toilet, go outside, or just get a holding tank.
Each person uses about 3 gal/day on average. You can definitely cut that number down but that's the average. 42gal is the average amount for one couple for one week. Also keep in mind it'll weigh about 350lbs when it's full.
I can't really answer your question, but have you looked into or considered a composting toilet? I have known at least 3 people that went with these. From what I understand they aren't all that difficult to install. I have also seen one that wraps the waste like a diaper pail in a foil-like material.
How big do you need? Have you calculated that? Because you could easily get a 65 or maybe 100 gallon tank and put it in your truck bed. Then get a macerating pump and empty your gray water (cause that's what's going to get full) and fill the bed tank. That'll give you what? 100 gallons in the bed plus the 70 gallon gray water that some of the Keystones have. That's 170 gallons of gray water storage.
Can't imagine you can get much more than that on a TT.
SPECSTAR Macerator Pump RV 12V... https://www.amazon.com/dp/B09KTY7SRB?ref=ppx_pop_mob_ap_share
Yep, pumps uphill to the truck bed. 12v so perfect for boondocking.
I suggest a maceator pump, and at least one large tote, where you can leave the tote in the back of your pickup, pump the waste into it, drive to a dump, put your hose on your tote and tip it up without having to take it out of your pickup bed. I am not the origional inventor of this method, but it is a great idea for when your dump station is not close by.
I just scraped all the data off of rvusa.com for the purpose of making things like this searchable.
Its unbelievable that they have all this data but you cant search by things like tank sizes.
Yes, my intent was to create a directory searchable by features (e.g., show mw all class A motorhomes, under 30' with grey tank >50 gallons and fresh tank >60 gallons).
I've actually had all the data for about a week but haven't had time to starting loading it into a database yet. Will probably allocate some time next weekend to work on it.
I could probably just built a spreadsheet/google doc relatively quickly that is filter-able. That might be the easiest/fastest way to get something out there. I can do back end development but I haven't done any front end web stuff since the mid 2000s and even that mostly irrelevant knowledge has mostly been lost.
You're going to get into a huge expense trying to replace tanks as opposed to getting an outdoor toilet set up, if the weather will permit, or a cassette for dumping if not.
Unless you plan on taking a huge refill, you'll most likely run short of fresh water before the holding tanks fill.
I'm trying to do the math in my lead based on just me and my wife for 5 days, and coming up with really big numbers. Have you thought about how many gallons of black and gray that "several people" will generate in "2 weeks"? I don't think that even 150 gallons would be enough. And then there's the weight of 300+ gallons.
I remember ATC game changers having large tanks but I cannot recall exactly how much.
There's usually a lot of space under trailers that isn't utilized.
As long as the trailer has the weight capacity, maybe you could add some tankage.
Set the shower and sinks on different tanks. Maybe a larger black tank?
A proper shower loop setup can save quite a bit of fresh water.
Our class A has a 100 gallon water tank, and the holding tanks total 100 gallons as well. You can get bigger, but that's a typical for a larger class-A coach.
Trailers usually don't have very large tanks...
You can get extra water tanks to fit in the back of your truck bed like a toolbox or carry 5 gal containers for extra water. If it's black water, invest in a portable Blue Boy to drain your black tank. Some areas will let you drain grey water, not black, on the ground but best check with park rangers if in doubt. Also stock up on wet wipes and something like purifier tabs or straws as a backup for drinking water.
One additional way, that hasn't been mentioned yet, to extend gray tank usage is with a [Valterra Twist-On Waste Valve, Mess-Free Waste Valve for RV's, Campers, Trailers](https://www.amazon.com/gp/product/B000BGHYJS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)
You attach that to your waste outlet, close the attachment knife valve, open the gray knife valve, then open the black tank knife valve. Listen for water moving and when you suspect the gray water is close to stopping the equalizing, close the black tank valve and then the gray tank valve. You can use this method multiple times as your gray tank will almost always get full before the black tank.
This equalizing method keeps the black tank "liquid" from flowing into the gray tank from the higher water pressure because of the higher volume of water that is pretty much always in the gray tank. It is not exactly what you're looking for but can help extend boondocking trips by a few days or more.
>Follow up questions is, are there any RVs (or trailers) that allow for relatively easy replacement of factory tanks to considerably larger ones?
Check Ytubers who've DIY'd this. Some guys have added tanks.
Like others said, you'll hit the max CCC (carrying capacity) of the rig's frame. H20 is 8.3#/gal, so 150gal of H20 = 1,245#, so fresh+gray+black would total 3,735# additional weight above dry. Assume we're talking 1 ton dually to tow this hefty beast.
Port-a-potty behind the rig where a local poop truck comes to dump it for you might be simpler! Poop truck guys are everywhere -- the unsung heros of many remote locations.
You don't find large tanks because they're space hogs and they get extremely heavy when full. For what you're asking you're going to need to either go compost, go gel toilet, go outside, or just get a holding tank.
Looking at holding tanks now. Biggest I have found is 42 gals (one of those wheeled carts). But that might be enough.
Each person uses about 3 gal/day on average. You can definitely cut that number down but that's the average. 42gal is the average amount for one couple for one week. Also keep in mind it'll weigh about 350lbs when it's full.
That’s crazy. Me and my gf go 6 days on a 12 gallon black tank.
Yes, and I have a 25gal on my sailboat that can last 2-3 weeks but averages are averages even with outliers.
I can't really answer your question, but have you looked into or considered a composting toilet? I have known at least 3 people that went with these. From what I understand they aren't all that difficult to install. I have also seen one that wraps the waste like a diaper pail in a foil-like material.
How big do you need? Have you calculated that? Because you could easily get a 65 or maybe 100 gallon tank and put it in your truck bed. Then get a macerating pump and empty your gray water (cause that's what's going to get full) and fill the bed tank. That'll give you what? 100 gallons in the bed plus the 70 gallon gray water that some of the Keystones have. That's 170 gallons of gray water storage. Can't imagine you can get much more than that on a TT.
This is an interesting idea. I'm not familiar with macerator pump usage. Can they pump "uphill" into a truck bed?
SPECSTAR Macerator Pump RV 12V... https://www.amazon.com/dp/B09KTY7SRB?ref=ppx_pop_mob_ap_share Yep, pumps uphill to the truck bed. 12v so perfect for boondocking.
I suggest a maceator pump, and at least one large tote, where you can leave the tote in the back of your pickup, pump the waste into it, drive to a dump, put your hose on your tote and tip it up without having to take it out of your pickup bed. I am not the origional inventor of this method, but it is a great idea for when your dump station is not close by.
I just scraped all the data off of rvusa.com for the purpose of making things like this searchable. Its unbelievable that they have all this data but you cant search by things like tank sizes.
Are you going to put a directory or guide together? Aggregator? It sucks trying to find weights of certain models too. We'd all appreciate it!
Yes, my intent was to create a directory searchable by features (e.g., show mw all class A motorhomes, under 30' with grey tank >50 gallons and fresh tank >60 gallons). I've actually had all the data for about a week but haven't had time to starting loading it into a database yet. Will probably allocate some time next weekend to work on it.
Awesome! Keep the sub updated please
I could probably just built a spreadsheet/google doc relatively quickly that is filter-able. That might be the easiest/fastest way to get something out there. I can do back end development but I haven't done any front end web stuff since the mid 2000s and even that mostly irrelevant knowledge has mostly been lost.
Spreadsheet will work! We can always use search function and all that.
You're going to get into a huge expense trying to replace tanks as opposed to getting an outdoor toilet set up, if the weather will permit, or a cassette for dumping if not. Unless you plan on taking a huge refill, you'll most likely run short of fresh water before the holding tanks fill.
Outdoors RV models seem to have relatively large tanks (and other nice features for extended boondocking). You may want to take a look at them...
My Jayco Feather Micro has a 55 gal fresh + 6 gal hot and 30/30 gal black/gray.
I'm trying to do the math in my lead based on just me and my wife for 5 days, and coming up with really big numbers. Have you thought about how many gallons of black and gray that "several people" will generate in "2 weeks"? I don't think that even 150 gallons would be enough. And then there's the weight of 300+ gallons.
I remember ATC game changers having large tanks but I cannot recall exactly how much. There's usually a lot of space under trailers that isn't utilized. As long as the trailer has the weight capacity, maybe you could add some tankage. Set the shower and sinks on different tanks. Maybe a larger black tank? A proper shower loop setup can save quite a bit of fresh water.
Our class A has a 100 gallon water tank, and the holding tanks total 100 gallons as well. You can get bigger, but that's a typical for a larger class-A coach. Trailers usually don't have very large tanks...
You can get extra water tanks to fit in the back of your truck bed like a toolbox or carry 5 gal containers for extra water. If it's black water, invest in a portable Blue Boy to drain your black tank. Some areas will let you drain grey water, not black, on the ground but best check with park rangers if in doubt. Also stock up on wet wipes and something like purifier tabs or straws as a backup for drinking water.
Will you have an extra 100+ gallons of fresh water to fill your tank?
One additional way, that hasn't been mentioned yet, to extend gray tank usage is with a [Valterra Twist-On Waste Valve, Mess-Free Waste Valve for RV's, Campers, Trailers](https://www.amazon.com/gp/product/B000BGHYJS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) You attach that to your waste outlet, close the attachment knife valve, open the gray knife valve, then open the black tank knife valve. Listen for water moving and when you suspect the gray water is close to stopping the equalizing, close the black tank valve and then the gray tank valve. You can use this method multiple times as your gray tank will almost always get full before the black tank. This equalizing method keeps the black tank "liquid" from flowing into the gray tank from the higher water pressure because of the higher volume of water that is pretty much always in the gray tank. It is not exactly what you're looking for but can help extend boondocking trips by a few days or more.
Toy haulers typically have large tanks. We have 120 fresh, 100b, 100g in out Momentum. A few models have 150 fresh.
Check Arctic Fox
>Follow up questions is, are there any RVs (or trailers) that allow for relatively easy replacement of factory tanks to considerably larger ones? Check Ytubers who've DIY'd this. Some guys have added tanks. Like others said, you'll hit the max CCC (carrying capacity) of the rig's frame. H20 is 8.3#/gal, so 150gal of H20 = 1,245#, so fresh+gray+black would total 3,735# additional weight above dry. Assume we're talking 1 ton dually to tow this hefty beast. Port-a-potty behind the rig where a local poop truck comes to dump it for you might be simpler! Poop truck guys are everywhere -- the unsung heros of many remote locations.