Real-world lessons from our van

Our setup

Our ProMaster carries about 39-40 gal of fresh water. We use a pump-fed kitchen and indoor 30 x 24 in shower, a cassette toilet, an underslung grey tank with electric dump, and a Clearsource Ultra Mini treatment train with UV at the drinking faucet.

What worked

Forty gallons gives two people meaningful off-grid freedom without turning every dish into a crisis. The indoor shower is a quality-of-life upgrade. Point-of-use UV preserves whole-system flow, and the cassette avoids a black tank/dump-hose system.

Travel reality

Across Mexico and Central America, refill quality and connector availability vary more than any brochure suggests. We learned to ask about the source, watch sediment, keep adapters, treat drinking water as a separate risk decision and never assume that clear water is potable.

Tradeoffs and changes

A full tank adds roughly 334 lb/151 kg. The underslung grey tank and electric valve are convenient but exposed to road debris, freezing and actuator failure, so manual recovery matters. Filters need space, spares and maintenance; more stages also mean more restriction.

Would we repeat it?

Yes to the capacity, indoor shower, cassette toilet and drinking-tap treatment. We would prioritize access panels, measured tank levels, easier full-system draining, a documented manual grey-dump backup and even more deliberate separation between fill-side sediment control and drinking-water purification.

Dave's bottom line

The best feature is not the 40-gallon number. It is the combination of usable storage, an indoor shower, a simple toilet, a practical grey system and drinking-water treatment that fits the places we actually travel. But the system stays trustworthy only when it is accessible, maintained and used with honest source judgment.

CHAPTER CHECK

• I can explain the purpose and failure mode of each item in this chapter. • I know which manufacturer limit or water-quality claim controls my choice. • I added the valve, access, drain, measurement or maintenance task to my drawing/checklist.