Which Wheel Well Water?


Water Tank Dilemma:

Promaster 1500 118" WB really shows off it's tinyness at the back of the van. The 136" WB is the same van, just with length tacked onto the back. Makes sense. No big deal. Except when you want to wedge in a water tank.

There are two wheel well water tanks that fit the Promaster, one from Curious Campervans and one from The DIY Van.

The Curious Campervan tank is custom molded to fit Promaster wheel wells.

The DIY Van tank generically fits Promasters, Sprinters & Transits.

I have the dimensions of a generic Promaster 118" WB, but it's always good to get the measurements from the place where the tank will actually live. Too bad my cousin isn't near the van and I'm in WeHo all day. So, generic measurements will have to suffice for now.

Caveat: on the wall in the back corner of the driver side there is a factory compartment for the tire jack. It gets in the way of any tank I want to use, but it can be removed. So, the sketches below assume we've torqued it out of the corner.

2nd Caveat: In reality the tanks taper inwards to fit the wheel well, but I'm not great with graphics programs, so mine are just squared off inside - this is just to get a feel for the outer fit, really.

3rd Caveat: I am assuming 1-2" of insulation and plywood on the walls, so positioning the tanks on the sketch about that far away from the walls and wheel wells.

After speaking with one of the lovely Canadian proprietors of Curious Campervans about dimensions and external fittings, I was scared that the driver side tank might not fit on the driver side. (The sketch below doesn't include the 1/2" external fittings or the plumbing fittings that could be used.)

He suggested that if the Driver Side tank didn't fit on the driver side, to try the passenger tank on the driver side. That's not ideal, because then precious space is lost in front of the wheel well where the galley kitchen will reside.

So far we've been planning to have the driver side be the "WATER" side and passenger side be the "ELECTRICAL" side. We're trying to distribute the weight of the van equally as well as simplify the placement of amenities. The fresh water tank should live closest to the sink and shower. The electrical set-up should live closest to the DC-powered Air Conditioning unit. Water is very heavy, but so are battery banks. We don't want two really heavy build elements on the same side of the van. We also want to limit running pipes and wires under the floor.

For kicks, I sketch-fit the passenger side tank on the passenger side.

When I looked at the fit of the DIY Van tank, it seemed like an awful waste of space.

I called The DIY Van to ask about fit for the 118" WB and the gentleman I spoke with was kind of rude, like "How should I know if it'll fit? I sell hundreds of these a year. I don't know which vans they go into."

In contrast, the lovely gentleman at Curious Campervans was sweet, talked to me twice, offered to hold the one tank they had left in stock for me until the end of the day when my cousin can measure the van in person. He also went into the shop and measured the tanks and their onsite promaster to help me firgure out how far out the fittings would protrude.

So, Curious Campervans -

PROS: Better fit, better use of space, 22 gallons capacity, one DRIVER side tank in stock, nice guys running the place, $285.

CONS: Might be too tight of a fit, if I can't decide by the end the day the tank will definitely be gone tomorrow.

DIY Vans -


CONS: Wasted Space, not a great fit, 20 gallons capacity, none in stock right now, backordered for weeks, the guy I spoke with was kind of a jerk, $355.

Seems to be a no-brainer to me. But I'm waiting on the cousin numbers...


After a very helpful back & forth of emails and texts and an 1+ hour drive down to measure FifVANella myself, I sent pictures of the van measurements to Jordan & Taylor at Curious Campervans and they sent me back pictures of their promaster's measurements.

They thought it would fit, I thought it would fit. So, I bought it! They're sending it out tomorrow! Yay! 22 gallons of fresh water on the WATER side of my van!

UPDATE 2: The tank arrived today! Driving it over to FifVANella later tonight. :-)

UPDATE 3: It fits!

UPDATE 4: I wound up ordering a bunch of other promaster and van-conversion specific products from the folks at The DIY Van, who could not have been more professional. Maybe they were having a cranky day (hasn't all of 2020 been one very long cranky day?) when I called about the water tanks. In any event, I got the right tank for FifVANella and the right other stuff, too. ;-)