Join cab to box for pass-thru on u-haul truck

[cabnetguy]

Hi everyone,
I have recently purchased a E-350 17' u-haul truck to convert to a RV. This Truck will not be converted to 4x4, but will have Weldtec's 6" lift so that my wife and I can travel rough dirt roads. I would like to remove the fiberglass cab back and slide the box forward to fasten to the cab so that I can cut a pass-thru like on class C RVs. I know that this is done on standard box trucks that only see asphalt, but will I have problems with chassis flex in rougher conditions? I tried calling custom truck body shop, but they were not to helpful so I thought that I would check with the you guys here for some insight.

Thank's

 

[The Artisan]

Does it really need to be connected. Sliding door on cab and one on the box. Safe and no worries about it being attached. If you take the box off and want to use as a flatbed you can still lock the sliding door.
Kevin

 

[cabnetguy]

Thanks for the reply.

I hope that the box will never have to be removed after the build. My wife would like to be able to go to the back of the camper while traveling if needed, would also be good for parking in nasty weather. My wife is great about not asking for much, so when she does I try real hard to satisfy her.

 

[The Artisan]

Thanks for the reply.

I hope that the box will never have to be removed after the build. My wife would like to be able to go to the back of the camper while traveling if needed, would also be good for parking in nasty weather. My wife is great about not asking for much, so when she does I try real hard to satisfy her.

Is the box right against the cab? What I am saying is make a pass through but they do not really need to physically connect. If there is some space make a cover off the box to shield rain. No real reason to use a rubber bellow to make the cab and box connect. Best to make each opening independent, imo
Kevin

 

[cabnetguy]

The truck is a cutaway cab chassis so the cab has a flange already there to bolt to. It currently has a fiberglass cab back bolted on. I was planning to remove the fiberglass cover and slide the box forward and bolt to the box. Attached is a picture of a cab similar to mine, but without the fiberglass cab back.

 

[The Artisan]

The truck is a cutaway cab chassis so the cab has a flange already there to bolt to. It currently has a fiberglass cab back bolted on. I was planning to remove the fiberglass cover and slide the box forward and bolt to the box. Attached is a picture of a cab similar to mine, but without the fiberglass cab back.

Ah got ya I thought both were enclosed seperate units.
Kevin

 

[dwh]

Random thoughts...

On rough roads, the frame will flex. Better if the cab to cabin connection flexes.

Moving the box forward will likely be easier said than done. Details like fuel fillers, mounting obstructions and whatnot may well make it a PITA.

Personally, I'd make a smaller opening with a seal around it. Big enough to pass through, but not too big.


Or, do what you have in mind and let us know if anything breaks out in the real world.

 

[Vandit]

I would definitely go through some of the ambo threads. On several of the ambo build threads they have pics of the pass through. I can't remember right off hand, but there's one or more threads where they modified the opening or reconfigured it and had pics of it without all the interior trim installed so you can see what's going on. I'm sure you could message the owner for more info/additional pics.

Moving the box forward will likely be easier said than done. Details like fuel fillers, mounting obstructions and whatnot may well make it a PITA.

? x2 on this. Moving the box foward may be way more work than it's worth. In addition to what dwh said already, I would think that relocating the wheel wells would be a pretty big headache depending on what type of box you're working with and how far you're moving it forward.

Leaving the cab extension on would provide you some additional cab storage and the ability to recline your seat back to a comfortable angle. I've driven a few standard cab box trucks (van chassis) across the country and the upright seat back angle and the inability to just move the seat itself back far enough for my legs made for a long, miserable ride.

 

[cabnetguy]

That's what my concerns are. The fuel filler will not be bad to handle. The box mounts are not a problem. Worst part will be cutting the bumper mounts and re welding. I have a welder so I should be able to handle that. My main concern is flex from the solid mounted box to the cab that has regular rubber mounts. Ryder trucks have their boxes fastened the cab and I have never noticed signs of stress, but I'm pretty sure they don't see very many dirt roads. The seat position won't be a problem I'm not that tall. The box doesn't have wheel wells, just flat plates and I will be lifting the truck with weldtec's kit anyway. But this is why I posted, to get feedback and poke holes in the idea.

 

[dwh]

Jeez, yea...wheel wells. That's what I get for replying on my first cup of coffee...didn't even think of that.

 

[Vandit]

Sounds like you've already thought through some of the most glaring issues. In that case I say go for it. I would definitely consult a few of those ambo threads. There are several that feature a decoupled pass through solution and there was one where someone even found a source for a replacement rubber seal. If I can find it, I'll post it up.

 

[Ozrockrat]

If you go with installing a rubber boot (which would be my suggestion) you can buy it from www.fixmyambulance.com

I got a replacement boot for mine from them and it was reasonably priced and quickly delivered.

As another suggestion if you go that way would be to put a canvas type boot over the rubber boot to reduce the noise and protect the rubber.

 

[cabnetguy]

Ozrockrat, Is this the material that you are talking about ? http://www.fixmyambulance.com/product-p/uni-ed-5383.htm

Also I just remembered that Burlydirtyhippy did what I am talking about on his build. I posted on his thread to see if he has had any problems now that he has had his truck on the road for a while.

 

[Burlydirtyhippy]

I didn’t realize your box was separate already, thought you just wanted to open up the front wall. I would think keep the box as is and open up the pass through and seal it with a rubber boot....

 

[cabnetguy]

Found the seal that Ozrockrat mentioned, then found the company that manufactures it. They have several sizes for different gaps. I agree with you guys, the flexible seal is the way to go and save a butt load of work.
Thanks for all the help!