NW Conversions 36 Gallon Wheel Well Water Tank - Centered (SP-C-36)

The biggest centered tank NW Conversions makes: 36 gallons over the wheel hump, installable on either side.

Thirty-six gallons is genuinely a lot of water for a van — long enough for two people to run an indoor shower for a week, or for a family to stop planning trips around fill points. It fits in the same 48" length as the 24 gallon tank; the extra volume comes from going to a full 16" square section.

Be honest with yourself about weight before you order. Full, this tank is roughly 330 lb. On a 3500-series chassis that is fine. On a loaded 2500 with a rack, a full galley and two adults it can be the thing that puts you over your rear axle rating. Weigh the van if you are close.

Should you buy this tank, or a different one in the range?

• Buy the SP-C-36 if you want the most centered capacity available and your payload budget can take 330 lb.
• Buy the SP-C-24 if you would rather have the aisle space back — it is 3" shallower.
• Split the volume across an SP-C-24 inside plus an undercarriage tank if you want capacity without the interior bulk.

Confirmed fitment

Specifications

These tanks are not pressure vessels. They must be vented to atmosphere — a sealed tank will balloon on a hot day and collapse inward when the pump draws it down.

What ships to you

• (1) SP-C-36 36 gallon rotomolded tank
• Fittings, hose and mounting hardware sold separately

Installing it: what actually happens

A 16" square section is stiff, which helps — but it also means the tank is happiest sitting on a continuous base rather than bridging between two cross members. We build a full-length plywood pan and lay closed-cell foam between the pan and the tank so it cannot chatter.

Think about how the water behaves. Thirty-six gallons unbaffled sloshes hard under braking. Keeping the tank low and strapping it tight matters more here than on any other tank in the range.

• Full-length base pan, foam interface, two or three straps.
• Open only the ports you need; 2-1/8" hole saw on the bench.
• Check your rear axle GAWR against a full tank plus passengers and gear.
• A level sender in the top port earns its keep at this capacity — guessing gets expensive.

Questions we get asked about this part

How much weight am I adding to the van?

Water weighs roughly 8.34 lb per gallon, so 36 gallons is about 300 lb of payload once full, on top of the dry weight of the tank. Put that number in your build budget before you order rather than after — it is the most commonly forgotten figure in a van conversion.

Do I have to drill the ports myself?

On the wheel-well tanks the 1/2" NPT ports arrive open and ready to thread. The 1.5" ports are spun closed at the factory so you only open the ones your plumbing actually uses. Open them with a hole saw on the bench, before the tank goes anywhere near the van, and vacuum the shavings out. Plastic chips inside a fresh water tank are a mistake you only make once.

Does the tank need a vent?

Yes. It is designed to run unpressurized. Run a vent line from the top 1.5" port up above the maximum fill level and out through the floor or a body vent. Skip it and the tank will deform on a hot day, then pull its walls in when the pump runs.

Will this fit a 144" wheelbase Sprinter?

The tank is 48" long, which physically fits a 144 — but it consumes most of the usable wall behind the slider. In a 144 we normally spec the SP-C-24 and add capacity underneath the van instead.

Pairs well with

• Van water tanks and plumbing — the rest of the NW Conversions range

Sold and shipped by Campervan Parts R Us, the parts counter of Noke Van Co. — a working van conversion shop in Roanoke, Virginia. If you are unsure whether this fits your van, email us the year, model and wheelbase and we will check it against a build sheet before you order.