Hoisting cap by rack crossbars?

When I removed my shell in the past I lifted one corner at a time and slide boards between the shell and bedrails, then hoisted it up to my garage ceiling joists and drove out from underneath. It would be much easier to just hang it from my Yakima crossbars, attached with towers to Thule (I think) tracks in my ARE shell. But, while I think the 5 or 6 M4 or M5 screws attaching the tracks on each side are probably strong enough to take the weight, I'm not so sure about the Yakima tower attachments in tension. And it would be an expensive experiment if it fell, either on the truck as I'm pulling it out or on the floor of the garage. Does anyone do this regularly? My shell is cab-high and it's only 5' long so probably not much more than 175-200 lbs.

 

I just got an ARE CX series installed with thule cross bars. Thats the first thing I asked the garage that put it on. "can I suspend the cap from my garage ceiling?" He said definitely. The bars have a 300 lb limit, and the cap is only about 100 lbs (short bed, cab height). I'd say as long as you anchor it into ceiling joists you should be fine. I plan on doing the same thing this summer when it comes off.

 

OK, you first. Seriously the issue isn't really the load capacity of the rack, which is mostly the weight pushing DOWN on the rack, because you're effectively pulling UP on the towers between the crossbars and the tower bases. With my Yakima, it's just a clamp. If "feels" like it should be strong enough, but I'm just not sure. In addition, the hanging weight is pulling up on the bolts that connect the bases to the "nuts" the track slots, as well as the nuts pulling against the tracks; there's two of those per tower, but my educated opinion is they're probably OK. Finally there's the six or so bolts that go through the fiberglass; again, I suspect they're probably OK in tension. I've certainly driven with my RTT in some gorrible winds at 70 mph so it's seen some lift. Anyway, I think, I trust everything enough to use the bars to lift the cap off the bed, then I'll quickly add straps or boards under the bottom of the shell for safety and then release the load on the bars.

 

When you have a load pushing down on the bars, you’re distributing that load across the entire roof.

When you hoist by the bars, the only thing holding the weight is a handful of small bolts. You can feel how insecure it is if you ever try to lift the shell off the ground by the roof bars. I tried it once, never again. FWIW, my shell was 225 lbs (SnugTop XV) - 100 lbs for a shell is extremely light!

 

Here’s my thought - the weight rating for a cap includes the forces on it when you’re driving down a bumpy dirt road, in which case that includes whatever you have loaded on top pulling up partway through the bounce, so I’m thinking there’s some margin in the design.
That said, in my case, I ran lengths of unistrut on the inside of the shell beneath the tracks I installed, so instead of lifting on washers on 6 bolts per track, I’ll be lifting on two lengths of unistrut. I do like the idea of lifting by the rack just enough to slide boards underneath, then bolting the rack to the boards and lifting by that, though.

 

@dman100 I assume your crossbar loading in tension worked okay? I installed a hoist in my garage yesterday and I want to try something similar to help slide 2x4's into position between the truck box and camper shell.