Hitch Falure
 

Just a FYI, the below pictures were posted on the Grand Design Facebook page. It is still playing out on what caused the failure. A 2015 Momentum 380TH (42' long toy hauler with an empty weight of 15,500 lbs and 2950 lb pin weight) was being pulled by a Ford Dually. Speculation is that the Roto-Flex pinbox could have contributed to the failure. It happened at low speed, and neiher the truck or 5th wheel had any damage.

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Wow, that is some serious carnage! That is the aluminum version of the AUH if I am not mistaken. The trailer weight would be a bit of a concern for me being 15.5K lbs dry. I am a big supporter of the AUH, but with that size of a trailer I would probably have selected a B&W. Of course, you will never see me pulling that big of a trailer, I don't have enough ambition for something like that.

Just watched a video about the Rota-Flex because I am not familiar with it. I am not sure how the pin box would have effected the operation of the hitch enough to cause failure, but clearly something went wrong.

I just realized that the AUH in the picture is the goose neck version. That may have had something to do with it as well and between the goose neck mount, the Rota Flex box and the 15.5K dry weight trailer it was a perfect storm.

Keep us posted with the outcome. I have the steel 4 point mount 5th wheel rail version of the AUH and pull a 12K lbs trailer when it is fully loaded. I am still comfortable with hooking up my AUH and trailer and heading out.

I am wondering if that tube was dented at some point creating a weak spot to fail.

I don't have that weight but still am glad I have the steel model.

Wow, lucky he was going slow. That thing is mangled. Can't wait for the rest of the story.
I'll keep my B&W just feels more stout.

I'm a fan of my B&W as well. Giving the AUH the benefit of the doubt, the engineer in me suspects that bent pipe was damaged before failing. Maybe something heavy smacked it and put a dent in it. The dent may have been small and not noticed. The AUH design depends on undamaged pipes. I think my B&W could take a serious beating without significant weakening.

My guess. Overloaded hitch. GD 380TH GVWR is 19900. Wouldn't take much to exceed AUH rating of 4000# or so. Hope we find out what the cause of failure was!

Just looked at the AUH site and the aluminum version is rated for 4500 lbs pin weight and 24000 lbs gross trailer weight.
I've never seen a standard style hitch fail by being crushed by pin weight, if it's that's was caused by a dented tube it's as faculty design IMO.

Denny

Well at least on the plus side it's light enough for one person to remove from truck in one piece still.

More to it
 

I am a Mechanical Engineer.
There is certainly more to this story. That hitch is rated for that trailer. In order for a catastrophic failure like that to occur, it would have been subjected to forces far in excess of the design load. I certainly am not privy to AUH design specifications, however it is standard practice for hardware like a hitch to be designed with a high factor of safety in order to withstand any surge loads that may occur while towing. It most likely has a factor of safety of at least 2.0 . This means it could withstand loads at least twice what it was designed to carry as a working load.
This is most likely a case of prior damage that reduced the capacity, or improper installation of the hitch or mating hardware, or some violent event causing extreme stress like perhaps an accident.
It is highly unlikely that this would have occurred under normal operating loads and conditions.

It would be interesting to find out what really occurred.

I too think there is more to the story here. I do like my reese but want to switch to the Anderson. I think I would choose the steel design as well though.

We towed our Grand Design fifth wheel its first 12,000 miles with an Andersen Ultimate. The first thing the service manager told us when setting up our truck for us was that a Roto-Flex pin box was NEVER to be used with the Andersen hitch (and this came directly from Andersen). This is because the Roto-Flex, without the stabilizing influence of a standard fifth wheel hitch plate, does not keep the pin box plate on a horizontal plane. The MOR/ryde and Demco Glide Ride pin boxes are fine (we used the Demco). This person should have been steered away from the Roto-Flex.

Rob

If you look real close you'll see two bolts and steel plates that were installed to lock the roto-flex out.

I've said it before and I'll say it again. I don't understand the hype behind the Andersen. Yes you can lift it out easy, but do you really want the lightest possible means connecting your truck and trailer? I sure don't. I'll keep my Reese Elite.

I will pass on the dented cross member scenerio the Facebook group. That seems to me a very plausible cause, and ask the OP if that might have happened.

Yes, I was told that too, as my trailer has a Rotoflex pinbox too. They told me that I could tow it without the kit, but my experience would be better with the lockout kit.

https://andersenhitches.com/Products...ckout-kit.aspx