Best 40 Gallon Water Tank Solutions for RVs and Mobile Living
When choosing a 40 gallon water tank, consider durability, material safety, fitting options, and installation flexibility. This guide highlights five reliable options, suitable for RVs, campers, tiny houses, and mobile setups. Best for users needing durable, BPA-free potable water storage; better for those seeking flexible mounting and built-in fittings; choose this if you want NSF-certified options and USA-made tanks. A concise product summary table follows to help quick comparisons.
| Product | Brand | Volume | Notes |
|---|---|---|---|
| classAcustoms T-4000 40 Gallon | classAcustoms | 40 gal | NSF approved materials; many mounting orientations |
| Ameri-Kart 40 Gallon RV Tank (WT-5550) | Ameri-Kart | 40 gal | Potable water; multiple installation options |
| Class A Customs 40 Gallon Fresh & Gray Combo | classAcustoms | 40 gal + 46 gal | NSF certified; combo pack |
| Valley Industries T-040-WWSA-XL (40 gal) | Valley Industries | 40 gal | Translucent tank with volume markings |
| iSpring 40 Gallon RO Tank | iSpring | 40 gal | RO storage tank; versatile position |
ClassAcustoms T-4000 40 Gallon RV Tank
This 40 gallon tank from Class A Customs is designed for RV fresh or gray water storage. It uses NSF-approved materials and is suitable for potable water applications. The tank measures approximately 39.5 inches in length, 13 inches wide, and 18 inches high, and it supports mounting on multiple sides. Built-in fittings include two 1.5″ NPT and two 0.5″ NPT connections. Best for RV owners who want a US-made, sturdy tank with flexible installation. A limitation is that tolerance in dimensions may vary by ±0.25 inches due to manufacturing, so verify fit in your space.
Who it’s best for: RV owners seeking a durable, NSF-compliant tank with versatile mounting and clear inlet/outlet fittings. Best for those who want a freshwater or gray-water storage solution with straightforward installation.
Ameri-Kart 40 Gallon RV Fresh Water Tank (WT-5550)
Ameri-Kart’s 40 gallon tank is crafted in the USA from BPA-free materials and is intended for potable water use, including drinking and cooking. It features flexible installation options with built-in fittings (two 1.5″ NPT and two 0.5″ NPT). The tank is designed for durability, weather resistance, and hygiene, meeting IAPMO standards. Best for buyers who prioritize US-made construction and a straightforward, leak-proof potable water solution. Caution: ensure the fittings align with your RV’s plumbing layout to avoid compatibility issues.
Class A Customs 40 & 46 Gallon Combo Pack
This combo pack includes a 40 gallon and a 46 gallon tank, designed for fresh and gray water storage. Both tanks use NSF-approved MDPE resin with UV stabilization and include two 1.5″ NPT and two 0.5″ NPT fittings. Best for buyers who want a coordinated two-tank system for separate fresh and gray water lines. The main limitation is the need for more space and installation planning to accommodate both tanks in an RV or trailer.
ClassA Customs T4000-TO 40 Gallon Tank
This tank is made in the USA from NSF-certified food-grade materials and is designed for potable water use in RVs, motor homes, sprinters, and trailers. It offers multiple installation options with built-in fittings (two 1.5″ NPT and two 0.5″ NPT). It is described as thicker than many OEM tanks for improved durability and is NSF/IAPMO-compliant. Best for buyers seeking a USA-made, rugged tank with reliable fittings. Limitation: check the thickness and weight for your storage area to ensure mounting support.
Ameri-Kart 36 Gallon RV Fresh Water Tank
Although slightly under 40 gallons, this Ameri-Kart model is a popular alternative for those prioritizing a compact size with potable water compatibility. It is made in the USA from BPA-free materials and includes fitting options (two 1.5″ NPT and two 0.5″ NPT). It meets IAPMO standards and is designed for durability and hygiene. Best for smaller RVs or tighter installations where a full 40-gallon footprint is unnecessary. Caution: capacity is 36 gallons, not a full 40 gallon tank.
Buying Guide: Key Purchase Considerations
- Material safety: Look for NSF/ANSI certifications or BPA-free plastics to ensure water safety for drinking and cooking.
- Fittings and access: Check the number and size of built-in fittings (1.5″ NPT and 0.5″ NPT are common) and whether they fit your plumbing layout.
- Mounting flexibility: Tanks that allow multiple orientations simplify installation in limited spaces typical of RVs and trailers.
- Durability: Consider MDPE or other robust plastics, and whether the tank is UV-stabilized for long outdoor exposure.
- Dimensions and capacity: Confirm exact length, width, height and total volume to fit your storage area; tolerances may vary by ±0.25″ during manufacturing.
Practical Buyer Questions
- What is the best tank for potable water in RVs? Look for BPA-free and NSF-certified tanks designed for drinking water.
- Do these tanks come with pre-installed fittings? Many do; verify the sizes and positions to ensure compatibility with your system.
- Is a combo pack worth it? For separating fresh and gray water, a combo pack provides matched dimensions and materials, but requires more space.
- Can I mount these tanks in any orientation? Some tanks are designed to sit on any side; confirm mounting options before installing.
- What maintenance is required? Regular inspection of fittings and seals helps prevent leaks and contamination.
- Are these tanks made in the USA? Several models are manufactured in the USA and emphasize durable, high-quality materials.
Note: The product data above reflects manufacturer descriptions. No hands-on testing or user reviews are included. Always verify compatibility with your vehicle’s existing plumbing and mounting space before purchase.