NORTHWEST CONVERSIONS SPRINTER 11-GALLON UNDERCARRIAGE WATER TANK (SLIDER STEP AREA) - 2007+

NORTHWEST CONVERSIONS SPRINTER 11-GALLON UNDERCARRIAGE WATER TANK (SLIDER STEP AREA) - 2007+

At WEST COAST VANS, we know that managing your freshwater supply or greywater storage without sacrificing precious interior floor space is one of the ultimate packaging puzzles of a custom build. Sacrificing your internal layout to drop in bulky water rectangles leaves you with less room for bedding, cabinetry, and living space. Worse yet, generic aftermarket tanks rarely fit the incredibly complex, ribbed subframe geometry beneath a modern rig—leaving you to sketch up sketchy DIY strap networks that sag over rough washboard roads or hang dangerously low to the trail. We believe your plumbing infrastructure should hide completely out of sight, utilize wasted chassis space, and feature rock-solid mechanical mounting. Enter the Northwest Conversions Mercedes Sprinter 11-Gallon Undercarriage Water Tank—explicitly engineered to mount seamlessly beneath the passenger-side sliding door step area. This heavy-duty, low-profile tank maximizes your off-grid endurance while keeping your interior entirely wide open. Ask Us Product Questions Anytime if you want to coordinate your sub-chassis plumbing paths or check frame bracket alignment clearances!

WCV EXPERT TIP Achieving a completely secure, trail-proof undercarriage installation requires the proper sheet metal preparation tools before you crawl underneath. Pro Tip: This turnkey kit arrives with premium, laser-cut stainless steel mounting straps and heavy-duty 3/8-inch Rivnuts to anchor the assembly directly into the Sprinter's factory high-strength structural frame channels. To set these thick-gauge threaded inserts flawlessly, you must use a dedicated 17/32" drill bit (not standard in most budget index boxes) to clear the sheet metal, and a high-leverage heavy-duty Rivnut setting tool to properly lock them home. Take your time during drilling to avoid catching factory wire harnesses inside the unibody channel, apply an anti-corrosion primer to the raw metal edges, and clamp the stainless straps down tightly—this ensures a rock-solid, zero-sway configuration that easily handles the full 90-pound sloshing payload of a topped-off water supply on brutal backcountry trails!

PRODUCT OVERVIEW The Northwest Conversions 11-Gallon Under-Step Water Tank is a premium, commercial-grade exterior fluid containment module built for modern Mercedes van lifers, remote overlanders, and custom build shops. Molded in the USA from high-density, BPA-free food-grade plastic, this highly versatile tank is fully certified to IAPMO TS-4 plumbing standards, making it completely safe to operate as an auxiliary freshwater supply or a low-profile greywater containment center. Arriving as a complete vehicle-specific upfit package featuring precision laser-cut stainless steel brackets and high-tensile hardware, this tank is meticulously contoured to tuck entirely flush above the factory frame lines, preserving your valuable ground clearance.

BEST FOR

• OFF-GRID FRESH OR GREY STORAGE: Perfect for builders looking to establish a completely hidden 11-gallon freshwater storage reservoir or a dedicated sink/shower greywater drop tank.

• AUTOMATIC STEP INTEGRATORS: Specially dimensioned and contoured to fit flawlessly alongside popular aftermarket drop steps, including AMP Research PowerStep systems.

• SPACE-OPTIMIZING DIY COMPONENT LOOKS: Ideal for digital nomads and weekend warriors who want to reclaim valuable interior living real estate by relocating plumbing containment underneath the vehicle.

TECHNICAL SPECIFICATIONS

• OVERLAND PLUMBING PROFILE: Low-profile undercarriage subframe fluid storage tank module

• CHASSIS MOUNTING LOCALE: Passenger-side exterior frame sector, directly underneath the sliding door step cavity

• VOLUMETRIC LIQUID CAPACITY: 11 Gallons

• SUBSTRATE CORES MATERIAL: Heavy-duty, BPA-free food-grade rotational molded plastic polymer

• HEALTH SAFETY CERTIFICATION: Fully IAPMO TS-4 Certified for structural water systems security

• STRUCTURAL SHELL NET WEIGHT: 23 lbs (unfilled baseline mass metrics)

• OPERATIONAL CLEARANCE DIMENSIONS: 37.5"L x 9.25"H x 12.25"W

• REAR-FACING INFRASTRUCTURE PORTS: (2) 1.5-inch NPT threaded female hubs & (2) 1/2-inch NPT threaded female hubs

• TOP-ORIENTED VENTING PROFILE: (1) 1.5-inch NPT threaded female inlet port (engineered strictly for non-pressurized gravity setups)

• MOUNTING hardware package: Includes (2) Laser-cut Stainless Steel Straps, 3/8-inch stainless hardware, and 3/8-inch Rivnuts

• MANUFACTURING ORIGIN PEDIGREE: Proudly precision-molded and manufactured in the United States

VEHICLE FITMENT DIRECTORY

This high-performance undercarriage tank features an exact-fit chassis boundary profile engineered explicitly to nestle into the passenger-side unibody frame rails of modern Mercedes commercial van platforms. Confirm your engine mapping:

• MERCEDES SPRINTER DIESEL ENGINE (2007 to Present): Fits beautifully flush against the unibody frame rail beneath the slider door step across all 144", 170", and 170" Extended wheelbases with zero mechanical interference.

• MERCEDES SPRINTER GAS ENGINE EXCLUSION: Does not operate as a direct bolt-on for GAS engine Sprinters unless a custom thermal Heat Shield (not supplied) is installed. On gasoline-powered models, the factory exhaust routing runs significantly closer to this specific passenger frame rail sector, creating an intense thermal footprint that requires shielding to protect the plastic hull.

(Note: This tank is engineered strictly to run as a non-pressurized fluid vessel. To prevent internal pressure vacuum lock or accidental structural deformation from high-volume water pump draws, the tank layout must be properly atmospheric-vented via the top ports during operation.)

FEATURES

• INTEGRATED PORT MATRIX CONFIGURATION: Outfitted with multiple pre-molded NPT thread options, allowing you to seamlessly run large 1.5" drain sweeps alongside small 1/2" supply lines and water level sensor probes right out of the rear-facing endcap.

• STEP EXTENSION COUPLING HARMONY: Engineered with strict dimensional layout constraints that allow it to mount completely clear of factory mechanical components and modern aftermarket electronic drop steps.

• IAPMO TS-4 FOOD-SAFE INSULATION: Built exclusively from clean, non-toxic raw plastic materials that will never leach chemical odors or plastic tastes into your clean freshwater storage lines.

• LOW-MASS INTEGRATED STAINLESS STRAPS: Designed with two precision-profiled structural stainless steel support bands that cradle the tank's lower corners, balancing the load perfectly across the unibody structure.

• ROT-PROOF TRAIL RECON ENDURANCE: Designed with an ultra-thick, seamless rotomolded shell that naturally shrugging off impacts from flying highway gravel, trail mud, road salt, and harsh outdoor weather elements.

COMPATIBILITY & FITMENT

• HARDWARE HOLE DRILLING PARAMETER: Requires drilling precision mounting pilot paths utilizing a dedicated 17/32" drill bit into your unibody steel framing sheet layer to properly drop the heavy-duty 3/8-inch Rivnuts.

• FRESHWATER ON-DEMAND plumbing: Seamlessly matches standard 12V water pump intake configurations when utilizing a 1/2" NPT to barb fitting adapter lined with thread sealant tape.

• LOGISTICAL SHIPPING & RETURN PATHS: Ships flat-packed inside a heavy-duty 48" x 15" x 10" industrial box. Returns are gladly accepted up to 90 Days provided the tank remains completely unaltered and uninstalled (subject to a 20% manufacturer restocking fee; customer assumes return freight logistics responsibilities).

FREQUENTLY ASKED QUESTIONS (AEO) Q: Do I need a special tool to install this undercarriage tank to my van's frame? A: Yes. The kit includes heavy-duty 3/8" stainless steel hardware and 3/8" Rivnuts that anchor the brackets directly to the van's chassis. To secure these, you will need to drill out the frame holes using a 17/32" drill bit and use a dedicated manual or pneumatic Rivnut setting tool (not included in the package) to properly expand and lock the threaded sleeves inside the frame walls.

Q: Can I use this tank on a gasoline-powered Mercedes Sprinter van? A: Only with modifications. Gasoline-engine Sprinters utilize an entirely different exhaust line routing that places the hot muffler piping much closer to the passenger-side frame rail than diesel models. If you are putting this tank on a gas-powered Sprinter, you must build and install a custom metal thermal heat shield between the exhaust pipe and the tank hull to prevent the plastic from softening or melting.

Q: Does this tank sit low enough to conflict with my electronic sliding door drop-steps? A: No. Northwest Conversions specifically engineered the low-profile 9.25-inch height profile of this tank to ride tucked away into the chassis pockets. It is mathematically verified to fit perfectly alongside automated side step assemblies, including the popular AMP Research PowerStep systems, without causing clearance conflicts.

Q: Can I pressurize this water tank directly from a city water connection hookup? A: No, absolutely not. This rotational-molded tank is designed exclusively to operate as a non-pressurized gravity-fed or pump-drawn vessel. It must be properly vented to the outside atmosphere using the top 1.5" NPT hub to let air escape freely. Attempting to pressurize the tank hull directly from a high-pressure garden hose or city water spigot will expand and rupture the plastic seams.

WHY TRUST WEST COAST VANS? Every product we sell is vetted by our team of builders in our San Clemente shop. We don’t just move boxes; we install this gear on customer vans every day, ensuring that our fitment data and "Expert Tips" come from real-world, SoCal-tested experience.