Roof Top Cargo Box Mounting Q


Officious Intermeddler
The van we’re buying has 3 fixed factory mounting points for cross bars, 36” apart along each side of the roof.

We want to mount the shortest cargo box on only the front and middle cross bars to keep the rear solar panel unobstructed.

Unfortunately, the only cargo boxes I’ve been able to find that we could mount on such a 36” spread are really long boxes that would block the solar panel.

We’ve not been able to find a short, stubby box that can be put on that long of a spread between the cross bars. All the short ones we’ve found require a a spread of @ 28” or less.

So two Q’s:

Does anyone know of a stubby box that’ll fit on the longer x bar spread?

(I’m not being lazy to ask y’all this because I’ve struck out after over four hours of web search)

More importantly, have any of you drilled your own mounting holes in the bottom of a cargo box to affix it to a cross rail and been fully satisfied with the end result? Is so, how did you reinforce the areas where you drilled the holes?

I obviously don’t want the floor of the cargo box to break at the drilled mounting points or for the box to fly off of the roof during higher speed driving…

And I can’t put length wise rail along the sides (which yes, would allow me to slide mounting x bars closer and thus meet the aftermarket box manf’s mounting specs) because then the van wouldn’t fit under my carport.

Any ideas?
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Rendezvous Conspirator
I went through a whole mess of cargo boxes on top of my van. All of them were bigger than I ended up needing, especially as I shed unnecessary gear and got more and more conscious about weight up high. They are also all TALLER than I wanted - the market seems to think that if you have a short-length cargo box, they need to make up the volume with height. At one point I was considering getting an ABS bike-transportation box and riveting on a hinge to make it into a short-height cargo carrier.

At one point, I had three cargo boxes for sale on craigslist at the same time - results of trying new things and eventually just shedding everything. Luckily for you, I took some photos when I was listing my crusty old boxes for sale!

As you can see, the mounting of the boxes (both Thule and Yakima) is pretty much a hole in the (very thin) plastic, backed up my some kind of plate to spread the load. There is no apparent "extra structure" at the mounts (other than some boxes having a recess molded in so that the box sits "down" over the crossbar - maybe for aerodynamics, but certainly the floor is not any thicker in those areas. From a "holding the box down" standpoint, I think you'd be just fine drilling new mounting holes and using the supplied hardware. The only problem I can think of is that none of these boxes had very thick bottoms. If you had a LOT of weight in the center of the box and a long span between the crossbars, it wouldn't surprise me if the box exhibited a little "bow" between the load points. Then again, maybe the bathtub shape will assist in keeping the box more or less straight.
cargobox1.jpg cargobox2.jpg

A side question: Is the roof on the van fixed or pop-up? I only ask because one of the reasons I kept shedding weight off my van roof was that I was constantly aware of how much the weight complicated the raising of the top. By the time I sold the van, I was down to only a small solar panel and a harbor freight aluminum cargo basket turned sideways as a teensy-weensy roof basket - both of these mounted right down as close to the 6-bar hinge as possible to minimize the "lever arm" effect.


Officious Intermeddler
Thank you Herbie that was incredibly helpful and detailed advice! 👍🏻 Exactly what I was hoping for.

We did look into getting a pop top rig since we were looking at the smaller models of vans, but the widest bed we could get on one (without gutting the interior and building out our own interior) was only 38 to 41 inches!

Just in case anyone’s interested BTW, there is a Nissan NV 200 pop top van for sale in Central Oregon with just that tiny couch/bed and no other interior build.

We’re getting the little ram pro master city cargo van. I can’t stand up in it but I have more than enough room to sit up comfortably on the side couch/bed.

The conversion was done by Cascade Campervans in Northern California and it’s the type of conversion that I would build myself, as far as the careful attention to detail and design, and how this little camper is put together is really quite impressive.


Officious Intermeddler
These vans were written up here previously:


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