Determining the exact Promaster cargo van interior dimensions you need is usually the first big hurdle when you're shopping for a new work rig or a base for a camper. It isn't just about how long the van is from bumper to bumper; it's about how much actual "living" or "working" space you have once you step inside. The Ram Promaster is a bit of a legend in the van world because of its boxy shape. Unlike some of its competitors that taper inward at the top, the Promaster stays wide, which makes it a favorite for people who don't want to feel cramped.
Whether you're a contractor trying to fit a specific shelving unit or a DIYer planning a queen-sized bed layout, you've got to get these numbers right. Let's break down the different configurations so you can figure out which one fits your life.
The basic configurations and why they matter
Before we dive into the specific inches and feet, it's worth noting that the Promaster comes in a bunch of different "flavors." You'll see them listed as 1500, 2500, and 3500. Don't let those numbers confuse you too much—they mostly refer to the weight capacity (payload) and the suspension, not necessarily the size of the box on the back.
The real magic happens when you look at the wheelbase lengths and the roof heights. Those are the two factors that actually change your interior dimensions. You've got the 118-inch, 136-inch, 159-inch, and the 159-inch extended wheelbases. Couple those with a standard, high, or the newer super high roof, and you've got a lot of math to do.
Floor length: How much "stuff" can you fit?
The floor length is probably the number people care about most. It's the difference between being able to haul 10-foot pipes or having to leave the back door open.
The 118-inch wheelbase (The "Shorty")
This is the smallest Promaster you can get. It's roughly the size of a large SUV, which makes it a dream to park in the city. The interior floor length here is about 8 feet (96 inches). It's perfect for a small delivery business or a solo traveler who wants a "minimalist" camper. You can't do a ton with the layout, but for a city-dwelling work van, it's incredibly nimble.
The 136-inch wheelbase (The "Middle Ground")
This is the "Goldilocks" of the Promaster world. It's long enough to feel like a real van but short enough that you don't feel like you're driving a bus. You get about 10 feet (120 inches) of floor length. Most people who build campers find this to be the sweet spot because you can fit a bed, a small kitchenette, and maybe even a tiny sitting area without much trouble.
The 159-inch wheelbase (The "Big One")
Now we're getting into the serious cargo space. The standard 159-inch wheelbase gives you roughly 12 feet (144 inches) of floor space. If you're a contractor, this is where you can start putting in full-sized workbenches. For van lifers, this is the configuration where you can finally have a "fixed" bed and still have room for a shower or a decent-sized kitchen.
The 159-inch extended (The "Hotel Room")
The "Extended" version uses the same wheelbase as the one above, but the body of the van actually hangs further out over the back wheels. This gives you a total floor length of about 13 feet (156 inches). It doesn't sound like much more, but that extra foot is huge when you're trying to squeeze in a gear garage or a full bathroom.
Interior height: Can you actually stand up?
Nobody likes crouching. If you're going to be spending any real time inside your van, the roof height is non-negotiable.
- Standard Roof: This gives you about 66 inches (5'6") of interior height. If you're on the shorter side, you might be okay, but most adults are going to have to stoop. This is usually fine for delivery drivers who are in and out quickly, but it's a tough sell for a camper.
- High Roof: This is the most common choice. It offers about 77 inches (6'5") of clearance. Even after you add a floor and a ceiling during a build-out, most people can stand up straight comfortably. It makes the van feel twice as big as it actually is.
- Super High Roof: A newer addition to the lineup, this one gives you a massive 86 inches (7'2") of interior height. It's massive. If you're tall or if you want to build some serious overhead storage, this is the one to look for.
The "Boxy" advantage: Width and wheel wells
The biggest reason people choose a Promaster over a Ford Transit or a Mercedes Sprinter is the width. The Promaster is notoriously "wide-hipped."
The maximum interior width is about 75.6 inches. But the number that really matters is the width between the wheel wells. In the Promaster, that's 56 inches. Why is that a big deal? Because a standard sheet of plywood or a pallet is 48 inches wide. You can slide a 4x8 sheet of material flat on the floor with room to spare on either side.
For van lifers, the width is the killer feature. Because the van stays wide near the ceiling, most people can actually sleep sideways (east-west) in a Promaster. In a Sprinter, you usually have to sleep lengthwise (north-south) because the van tapers too much at the top. Sleeping sideways saves you about two feet of floor space, which is a massive win in a tiny home.
Door openings and access
We can't talk about promaster cargo van interior dimensions without mentioning how you get things into the van.
The rear doors open 260 degrees, basically folding back against the sides of the van. The opening is about 60 inches wide and, depending on your roof height, can be up to 70 inches tall. This makes it incredibly easy to load in a pallet with a forklift or toss in a mountain bike without having to take the wheels off.
The side sliding door is also pretty beefy, with an opening width of about 49 inches. It's wide enough that you can actually load a standard pallet through the side door, which isn't something every cargo van can claim.
Real-world considerations: Walls and insulation
One thing to keep in mind is that the raw promaster cargo van interior dimensions provided by the manufacturer are for a completely empty, metal shell.
If you're using this for work, you'll likely add shelving or a bulkhead. If you're building a camper, you're going to add insulation, framing, and wall panels. You can expect to lose about 2 to 4 inches of width and height once you've finished the interior. If you're 6'2" and the high roof is 6'5", it's going to be a tight squeeze once you add an inch of foam board and a tongue-and-groove ceiling!
Also, don't forget the ribs of the van. The walls aren't perfectly flat; they have structural ribs that stick out. When you're measuring for cabinets or a bed frame, always measure from the narrowest point, not the widest gap between the ribs, or you're going to have a very frustrating day with your circular saw.
Wrapping it up
At the end of the day, the Promaster is a favorite for a reason. Its dimensions are incredibly "square," which makes it one of the easiest vans to build out or organize. You don't have to deal with the weird curves and tapers you find in other European-style vans.
If you're just starting your search, go to a dealership with a tape measure. Stand in the back of a 136-inch high roof and then a 159-inch high roof. You'll feel the difference immediately. Whether you need the agility of the 118-inch wheelbase or the massive "living room" feel of the 159-inch extended, knowing these promaster cargo van interior dimensions is the only way to make sure your project actually fits the space you have.
It's all about trade-offs—parking ease versus standing room, and payload versus floor space. But with the Promaster's boxy layout, you're getting some of the most usable cubic footage in the cargo van world.