Mercedes low-floor Sprinter chassis and similar options?

[Chance]

From the first time I saw a Dodge-based Xplorer class B camper van with a drop floor I’ve been interested in low floor designs as “one” option to raising the roof. If not to create all headroom at least in addition to a taller roof to provide some of the desired head room. Around the same time as the Xplorer vans (many decades ago) there were Transvans which also dropped the floor a considerable amount, but both of these generally had very little square footage of drop floor. They allowed upright standing but in a very limited space.

Later there seems to have been many Class Bs with dropped floor above the driveshaft. The area was much bigger and useable but the drop was limited to something in the range of 6 inches or so. That’s just an estimate on my part since I never measured it. Roadtrek still uses this design with many Chevy-based vans. By comparison Xplorers and Transvans dropped the floor well over a foot but had to miss the driveshaft or gas tank, respectively, hence why dropped floor was limited to a very small area.

Mercedes seems to be offering a low-frame Sprinter camper van chassis (in some markets -- pictures below) that is 205 MM (about 8 inches) lower. They accomplish this by going with an independent suspension rear axle and using a smaller fuel tank of 72 liters capacity. A nice bonus feature is they added 174 MM of rear track width (about 7 inches) which should work great for Class B+ campers. The point here is that there are “some” real advantages to going down versus up. Better fuel economy, very handling, easier entry and exit, less cross wind effect, and so on. And obviously there are some disadvantages too.

My question is this: If tall vans like Sprinter and ProMaster can offer 5-feet 4-inches of headroom in low-roof variants, would it make sense to drop the floor 6 to 8 inches in limited area to obtain standup clearance for shorter individuals? It seems technically possible if factory warranties don’t get in the way. Obviously for long-term camping you’d want all the room you can get in a much bigger van (it’s more cost effective), but for those who want a compact weekender or more of a travel van, increasing head room to 5’-10” to 6’-0” in a significant area of the floor plan may be enough. Especially if the van remained low enough to be garagable.

I believe Sportsmobile, like Roadtrek, also built vans with drop floors in the center just above the driveshaft. It was normally done with unitized body vans and not body-on-frame like the Ford Econoline. Does anyone have experience on how well these designs worked? Was it worth it or would it have been better to just raise the roof more to accomplish the same amount of headroom?

[yogiyoda]

The RAM ProMaster has front wheel drive. One of its big selling points is it's lower floor with a load height of 21 inches. That's 6 or 7 inches lower than Sprinters and E-Series.

https://www.youtube.com/watch?v=Loi2pFcA-YI

[jage]

Drop floor is more of a wheelchair/access thing than an RV thing, so I'd check with accessibility companies.

I don't think hydraulic driveshaft replacements ever got popular, but it's possible if you want to put the effort in and it's worth removing the driveshaft. By possible, I know it's been done for rock crawlers, not sure how feasible it is at highway speeds.

Also if you spend $15,000 dropping the floor vs $5000 raising the roof (made up figures) then it's not cost effective, e.g. as a manufacturer you're not going to hit a wide enough swath of the market to make it worth your while. B is already a specialty market, so I'm guessing there is not enough advantage- consider Sportsmobile's "garagable" version of the PH- not hugely popular as far as I can tell. In the end, as long as you're under 8' total height I think there are a lot of things you can better apply your money to. It is after all the US- doing something like a smaller footprint and profile with more room inside might go over in Europe, but here... well there really should be a class above A!

[Chance]

Let me put the question in proper context for clarity. I was thinking of a very common modification that has been done by many companies. Below is a picture I found of an old Roadtrek. Don't see why FWD would preclude such a modification. If anything it should make it easier.

[Chance]

Originally Posted by jage

........cut........

Also if you spend $15,000 dropping the floor vs $5000 raising the roof (made up figures) then it's not cost effective, e.g. as a manufacturer you're not going to hit a wide enough swath of the market to make it worth your while. B is already a specialty market, so I'm guessing there is not enough advantage- consider Sportsmobile's "garagable" version of the PH- not hugely popular as far as I can tell.

.........cut..........

Agree it would be a specialty market. However, a slight drop like shown above on older Roadtrek was relatively inexpensive. I tried to look up cost from Sportsmobile but couldn't find it; probably because they no longer do it on newer vans. I think it was in the order of $1000 or so (maybe someone will remember). Certainly it wasn't close to the range of $15,000. It wouldn't be something anyone would want to do to save a few dollars anyway when factory high-roof options are relatively inexpensive.

My wife can just stand in a low-roof Sprinter but I can't. If it had a Penthouse roof I probably could (haven't tried it) without the bed in place. If the PH wasn't needed for added sleeping, wouldn't it be easier to drop the floor 6 inches than to install a PH? Seems simpler to me but I don't know what was involved or if there were any issues like leaks, rust, etc....

[jage]

I would think a tray like that would be annoying- a trip hazard, etc. I thought you were talking about lowering the whole living space floor.

[yogiyoda]

Don't know much about lowering floors. But for any given amount of interior height, the RAM Promaster will have a significantly lower exterior height than a Sprinter. Detailed specs can be found online.

If that's not adequate, you can also try calling Sportsmobile, Roadtrek or those wheel chair conversion companies like BraunAbility to see if lowering the floor on these euro-vans is even a possibility.

And that last picture you posted looks like a lowered shower floor that would be covered up in normal use. Many Chevy Roadtreks today have a more uniformly lowered floor. Roadtrek owners generally are really happy with their vehicles except for road clearance.

[Chance]

Originally Posted by jage

I would think a tray like that would be annoying- a trip hazard, etc. I thought you were talking about lowering the whole living space floor.

Lowering the entire floor would be much better, but would require a lot more work. That's where the chassis described in initial post would come in for RV use. Eventually MB might incorporate something like independent rear suspension on Sprinter so it could lower floor but it's highly unlikely for commercial use where cargo carrying is the main objective. I don't think there would be enough of a market for regular vans.

For moving people around where the floor doesn't have to be of uniform level, MB has used lower floor designs for city buses for some time. It's nothing new. Recently they introduced a longer version of the low floor City bus which is a stretch Sprinter with dual rear axles.



I agree with you that a step adds to tripping hazard but don't see that as a great problem depending on interior layout. I'm not sure the Penthouse top wouldn't be as much of a hazard based on being a head knocker if the same standard was used. Not so much on Ford or Chevy because of chest-high elevation, but more so on Sprinter or future ProMaster. For people my height it would be right at forehead level. Also as to tripping, ProMaster already has a step behind driver and passenger seats built into design. Regardless you make an excellent point that everything else being equal a uniform floor is best.

[Chance]

Originally Posted by yogiyoda

Don't know much about lowering floors. But for any given amount of interior height, the RAM Promaster will have a significantly lower exterior height than a Sprinter. Detailed specs can be found online.

If that's not adequate, you can also try calling Sportsmobile, Roadtrek or those wheel chair conversion companies like BraunAbility to see if lowering the floor on these euro-vans is even a possibility.

And that last picture you posted looks like a lowered shower floor that would be covered up in normal use. Many Chevy Roadtreks today have a more uniformly lowered floor. Roadtrek owners generally are really happy with their vehicles except for road clearance.

If it is possible at all, I'd expect ProMaster to be easiest because of FWD. Plus as you stated its lower overall height would make it fit through 8-foot garage door with ease.

As to Roadtrek owners not being happy with road clearance, it shouldn't be because of the drop floor. The drop floor is above the driveshaft so it shouldn't affect ground clearance (unless they are doing something crazy I'm not aware of). Roadtreks do have a lot of low body work they use for storage that could be a problem with ground clearance though.

In older Roadtreks and similar designs from many manufacturers the drop floor area between the frame rails was typically not covered. I'm still looking for pictures of used Sportsmobile from the time this was done on Dodge and Chevy vans.

[yogiyoda]

Originally Posted by Chance

Roadtreks do have a lot of low body work they use for storage that could be a problem with ground clearance though.

Good to know. Always assumed the low clearance was related to the lowered floor.