I'm trying to mount a small RTT same as attached image on top of a 95' ZJ. I was thinking of using the factory rails with 4 factory cross bars. Anyone know what load the factory rails can support?

 

What's the width/weight on your RTT? Planning a side or rear opening?

OEM crossbars are weak, most RTT owners opt to use a heavier/stronger material to mount the RTT to. Yakima, Thule etc..

The problem with an RTT on a ZJ is the ZJ roof is arched. So with anything more than 2 crossbars, the center crossbars will want to push up on the center.. making the floor on RTT bow. This can destroy the RTT.. as can not having enough crossbars under, it can bow down.

If you have a narrow RTT, you may be able to get away with just 2 Thule etc.. just don't spread them too wide, you want enough support under center to not bow the floor.

My RTT is queen width @ 72" and even on the old XJ I'd have 4 crossbars to support it. To do so on my ZJ I'd need to make a flat platform rack and make a new mounting setup to the arched roof. Something like this.. pic borrowed from NAXJA.

 

With everything, we'd be around 450 pounds. I was planning side opening so we could still access the tailgate. I was thinking of making a small frame across four factory rails to distribute the load and keep the tent floor from bowing.

 

What brand and size RTT? How does it attach to it's mounting platform.. ubolts or throughbolts?

Any pics of the underside?

 

Generic name is Tepui. I'm buying it direct from manufacturer overseas, putting it in a friend's container, and it will be 60 days before I have it in hand.

 

OK, does it have mounting channels under floor or do you drill a hole through and bolt it down?

Considering it's a Chinese RTT I'd imagine a solid structure under the floor would be even more critical.. meaning I doubt they use better materials like the pricier tents.

I don't see the OEM crossbars being sufficient. I understand you may have a need to do something on the low $$ approach but last thing you want is to damage it. Search on EXPO and see what others are doing with their Tepui's..

Got a welder?? Wouldn't cost too much for materials to build something solid.

 

Yeah, I've got a welder and can fab no problem. I built this roof rack and the cargo rack in my sig for my XJ. GF sews as well, so we got most things covered if it's not perect. I did a little searching and am going to get either Thule or Yakima bars. Thanks for the input!