Water Weight Reference
The Tune M1 does not come with a water system, most owners carry 3–7 gallons in portable jugs or a mounted tank, which adds 25–58 lbs to your payload. Water weighs exactly 8.34 lbs per gallon, making it one of the most controllable variables in your payload budget. Use this table when planning your build:
| Gallons | Weight (lbs) | Context |
|---|---|---|
| 1 gal | 8.3 lbs | About the same as a large water bottle |
| 3 gal | 25 lbs | Minimum viable for a solo overnight |
| 5 gal | 42 lbs | Comfortable weekend solo / lean couple |
| 7 gal | 58 lbs | Common M1 default, good for 2–3 day trips |
| 10 gal | 83 lbs | Extended trip capacity, significant payload hit |
| 15 gal | 125 lbs | Large tank, meaningful payload commitment |
| 20 gal | 167 lbs | Only if you have the payload margin and a real refill problem |
The M1's payload calculator includes water weight: enter your gallons and see the impact on your truck's margin in real time. See the payload guide for the full picture of what eats into your rating.
How Much Do You Actually Need?
People consistently overestimate how much water they'll use in a truck camper. A few useful benchmarks:
- Drinking: ~0.5 gal/person/day minimum; ~1 gal/person/day if you're active in heat
- Cooking: ~0.25–0.5 gal/meal (boiling pasta, making coffee, etc.)
- Dish rinsing: ~0.25–0.5 gal if you're efficient
- Hand washing / hygiene: ~0.25–0.5 gal/person/day
- Outdoor shower: ~1–3 gal per shower depending on setup
A solo camper who isn't showering in camp often uses 1–2 gallons/day. A couple doing full camp cooking and hygiene might use 3–5 gallons/day. Calibrate for your actual habits.
M1 Water System Options
The Tune M1 does not include a built-in water tank, pump, or plumbing. Water storage is entirely owner-configured. This is actually an advantage, you carry exactly what you need for the trip and nothing more.
Portable containers (most common)
- Scepter or Wavian 5-gallon jerry can (~42 lbs full), the most popular choice. Durable, stackable, easy to fill. Sits in the truck bed alongside the sleeping platform or inside near the rear barn doors.
- Dometic GO Hydration Water Jug 11L (~$70, 2.9 gal, ~28 lbs full): a community favorite for owners who want something more refined than a jerry can. BPA-free LDPE, two openings (one for fill/clean, one with a spigot), webbed carry handles with built-in tie-down guides, and a quick-connect CPC fitting that pairs with the Dometic GO Hydration Faucet (see below). Designed to fit behind a truck wheel well. Less raw capacity than a 5-gal jerry can, but the integrated fittings and clean dispense make daily use noticeably easier.
- Reliance or Igloo 7-gallon container (~58 lbs full), good capacity for a couple or 2–3 day trip. Fits in the truck bed floor space next to the M1 platform.
- Multiple 1-gallon jugs: maximum flexibility; fill exactly what you need; easy to track usage. Takes more individual pieces but costs almost nothing.
- Collapsible 5-gallon container (Nalgene, MSR, or Reliance Fold-A-Carrier): stores flat when empty; great as a supplemental container without the dead weight when not needed.
DIY pump systems
Some owners add a simple water delivery system using the M1's T-track infrastructure:
- Hand pump spigot, a manual hand-pump on a jerry can; no electrical required; gets water out cleanly without lifting and pouring
- Dometic GO Hydration Water Faucet (~$100): a self-powered, USB-rechargeable faucet with a magnetic base that sticks to the truck body or any magnetic surface (an adhesive magnetic pad is included for non-magnetic spots). One-touch operation, automatic shut-off after about a liter, integrated LED for night use, and roughly 150L per charge. The reason it shows up in so many M1 setups: it solves the flow-rate problem. Pouring from a jerry can is wasteful and awkward; this gives you a controlled tap-style stream with no manual pump and no plumbing. Pairs natively with the Dometic GO Hydration Jug via quick-connect.
- Cheaper knockoff: USB-rechargeable bottle pumps (~$15–25): generic battery-powered dispenser pumps designed for office water-cooler jugs work surprisingly well on 3–5 gallon containers. One-touch operation with auto-shutoff after ~60 seconds, ~1,200 mAh internal battery good for 30–40 days of typical use, USB-C charging. Search "rechargeable water dispenser pump" on a non-Amazon site like Van Life Gear Company. Less polished than the Dometic, no magnetic mount, but they nail the flow-control problem at 1/5 the price.
- 12V water pump (Shurflo 2088 or similar, ~$40–80), 12V pump draws from a portable tank and delivers to a small camp sink or spigot; can be T-track mounted; draws ~3–5A when running
- Gravity-fed spigot: mount a container elevated on the T-track wall; spigot at the bottom; zero power required
None of these systems are plumbed permanently. They're modular setups that travel with you and come apart easily for cleaning or storage.
Grey Water Management
The M1 has no built-in grey tank. Most owners keep grey water simple because their water system is simple, if you're not running a plumbed sink, grey water is minimal.
Common approaches
- Portable grey tank / bucket, a collapsible bucket or small plastic tote under the cooking area catches any dishwater or handwashing runoff; empty at designated dump stations or per Leave No Trace guidelines
- Pack-it-out, for short trips, collect grey water in a lidded container and dispose at home or an approved dump site
- Dispersed camping disposal: in many dispersed camping areas, grey water (with biodegradable soap only) can be broadcast in small amounts 200 ft from water sources; check local regulations
Leave No Trace basics for grey water
- Use only biodegradable, phosphate-free soap (Dr. Bronner's is the community standard)
- Never dispose of grey water within 200 ft of any water source, trail, or campsite
- Strain out food particles before disposal; pack solids out
- In high-use or fragile areas (alpine, desert), always pack grey water out completely
Refill Strategy for Extended Trips
On longer trips, your refill strategy matters more than your tank size. Rather than carrying 15+ gallons (125+ lbs), many M1 owners plan around refill points:
- State/national park visitor centers: potable water available at most developed sites
- Dispersed camping areas: often near trailheads with water
- Town top-offs: stopping in any town with a grocery store or gas station
- Collapsible jugs: carry a 5-gallon collapsible as an emergency supplement without storing it full
Designing around a refill every 2–3 days often reduces the tank size you need, and meaningfully helps your payload budget.
Bathroom Solutions
The M1 has no built-in toilet. For most weekend campers this isn't an issue, as dispersed camping usually means using the outdoors. For longer trips, couples, or comfort-focused owners, a portable option is worth having.
Compost toilets
Compost toilets are the most popular "real toilet" solution in the M1 community, they require no plumbing, no grey water, and produce compostable solid waste. The trade-off: they require a bit of technique and are more involved to empty than a simple cassette toilet.
- Nature's Head, the most popular compost toilet in the vanlife/truck camper space. Separates liquid and solid, reducing odor significantly. ~$1,000.
- Air Head: similar design to Nature's Head, slightly different form factor. Also popular.
- OGO Composting Toilet: newer design with a built-in agitator and smaller footprint. ~$650.
Community tip for women: a SheWee or similar funnel is commonly used to direct liquid into the front separator on compost toilets. Many owners store the toilet outside the camper (in a waterproof bag at the rear of the truck bed) to free up interior space, bringing it in only when needed.
Simpler options
- Portable cassette toilet (Thetford Porta Potti, ~$50–120): simple, cheap, needs regular emptying into an RV dump station or toilet. Works well for weekend use.
- Wag bags / cathole kit, for dispersed backcountry camping where packing out is required. Light, minimal, no equipment needed.
- GoGirl / SheWee standalone, for standing urination in the field without a full toilet system.
Toilet weight counts too. A Nature's Head adds ~28 lbs to your payload budget. A Thetford Porta Potti is ~6 lbs empty. Factor this in if you're running tight on margin.
Community Tips
- Fill for the trip, not for the worst case. If you're going out for 2 nights, don't fill a 15-gallon tank — carry 7 gallons and save 66 lbs.
- Water is your most controllable payload variable. Battery, camper, passengers: those weights are fixed. Water is adjustable before every trip.
- Hot water options: Most M1 owners keep it simple. Common approaches: (1) Solar shower bag (5-gal, ~$10–20): lay on the truck roof in the sun for a few hours; 100°F+ water for a quick outdoor rinse; (2) Propane camp shower head. Mr. Heater or Zodi, ~$50–150. for instant hot water from a jerry can and a propane source; (3) Heat on stove: boil water in a camp pot for washing up; lowest-tech, works anywhere.
- Use a hand pump spigot on your jerry can. Pouring from a full 5-gallon can is awkward and wasteful. A $10 hand-pump siphon or a can with a built-in spigot (Scepter and Wavian both have spigot caps) pays for itself in water saved on the first trip.
- Track actual usage on your first few trips. Most owners find they use 30–50% less water than they budgeted. Once you know your real number, you can right-size your container and recover that payload.