Cheap Hitches, Big Loads, and Gravity

jaluhn83

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It makes you wonder when the stud that holds the ball on will give way. I have never heard of that happening though. My truck came with a gooseneck setup in the bed also. The ball for that has a huge threaded stud on the bottom.

1" threaded rod has a cross sectional area of around .65 in^2.... even low carbon steel has a tensile strength (UTS, ignoring YS for the moment) of around 60ksi, so around 40,000 lb tension or ~30,000 lb of shear force. Now, the tightening of the nut will put the stud under a fair amount of tension, but will also help hold the ball to the hitch and reduce shear stress actually put on the hitch ball stud.

Incidentally, the common 5/8" pin holding the hitch to the frame folks complain about being "too small" should take something like 25,000 lb of force to shear off, and that's assuming regular low strength steel.....
 

BDCarrillo

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And how much of a bump, shimmy, or brake issue would it take for a 10k or 20k towed load to pull 25 (NOT 2.5, my bad) kips on that pin? Shear isn't everything, deflection and fatigue can decrease the force required to exceed the modulus of failure. Goes back to the OP's point about "cheap" towing parts... I barely trusted a Harbor Freight adjustable height hitch and ball to pull a 3k boat/trailer behind my 6.4
 
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jaluhn83

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Not entirely sure where you got 2.5 kips, I was just doing a straightforward f/a shear computation off the uts to come up with a ballpark failure load. Yes, fatigue and such plays in but still it's not going to decrease it to where anything less than a significant collision will likely cause failure even with cheap steel.

Now, the engineering question I've always had with hitches is why the heck you'd want to use aluminum... but that's another topic.

Saw your edit - agree with towing parts - was just talking about the hitch pin since I've seen a decent number of folks that feel they have to replace it was a grade 8 bolt.... cheap/pooly engineered and constructed hitch parts are for sure scary.
 

BDCarrillo

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I was referring to the 25,000 pounds of shear on the 5/8 pin. Definitely agree on the oddity of aluminum hitches... The original post with photos should be proof enough to anyone that hauling equipment needs to be top notch and up to ***** for well over the load. Goofy bumper pulls or inferior hitches may work for a while, but it'll catch up to you.

And for a couple bucks I'd glady use grade 8 just for that peace of mind. Maybe that's an excessive safety factor but I'd be happier knowing it's there.
 

Tim4

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To the OP - what was the actual weight of that load? If you're going to the dump I'd assume you'd have a weight ticket. I'd be real curious to see what it was and what the tongue weight was if known. Also curious how much the truck squatted - I'd think it'd be pretty close to the bump stops. May be worth calibrating a bit so you can measure the squat and get some idea of load / tongue weight - I do this when I'd heavy with my flatbed.

Folks have a real tendency to get uptight about overloaded trailer, and for a decent reason - way too many idiots doing it without knowing what they're doing. I'm not as quick to judge, but there's some truth in what they say, particularly if it's a common thing and commercial work. I've run over 20k a few times with my rig, but it's few and far between and done very very carefully.... And of course critical to make sure that all your gear is up to spec and capable as there's little room for error as we have both discovered the hard way.

Worth looking into limitations for license classes too - here in CA the limit for anything but a class a commercial license is a 10k trailer. Now, I bet that gets regularly violated, and isn't too likely to be an issue for an occasional recreational trip, but if you're commercial it's another ball game.

I do carry the proper license for this load, and have had that class of license since 1980.

The landfill was closed at that time of day and it was all rock and dirt so the load was used for fill on a nearby project. Based on my seat feel of this load, I believe that it would have scaled at or around 20,000 pounds GVCW. The tongue weight was heavier than normal but not to the point of being of concern. I am aware of the dangers and cautious with every load that I pull, just a bit moreso with this one.

Bad things happen with even the best of intentions and equipment. I am aware of that but I do appreciate that we are not all created equal and some have more experience than others with respect to operator capabilities.

I have a policy and there are procedures in place for loads that I deem unsafe. If involves a roll back capable of hauling the load with appropriate back charges to the customer so I don't ever put myself in a situation that I feel is unsafe.

It is my opinion that the tongue weight was too great for the off road conditions leading to the fill site. It is my belief that this failure occurred in a somewhat controlled manner and serves mostly as a wake up call for me. I do this all the time and have been doing it for a long time and this was a situation that I have just never experienced before.

My apologies to the group for posting in the wrong section, although the little 6.9 with C6 had no issues whatsoever pulling the load. To those offended or that object to me sharing my real world experience with the group, I apologize as well.

It is my hearts desire that I , and perhaps others, can learn from this experience.

Thank you for your consideration.

Tim
 

Black dawg

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20k gvcw, I was picturing a way bigger load. I can see why you would be surprised to see that failure with that load.

Saw a load that made me laugh this weekend, a dodge (imagine that) pulling a goosneck with a smallish dozer (probably 21-24k dozer and trailer). THe funny part was the dozer was entirely in front of the trailer axles, and the poor dodge (dually) was completely smashed, to the point it was probably ruining the bump stops. Cant imagine how much weight was on the back of that truck.
 
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sjwelds

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Or my personal favorite: this guy that lives close to here does backhoe work for a living. has one of those fairly big Case backhoes. Has a nice bumper pull pintle hitch tandem dually trailer to haul it on. Most of the time he pulls it with his Freightliner or whatever it is, but now and then you'll see it behind his 3/4 ton Chevy pickup. the pickup doesn't even have a Dmax in it! A 6.0 gasser! Not even a one-ton pickup!

I've seen the receiver hitch on it. It has a permanent downward angle to it...................LOL
 

cpdenton

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Sometimes bad things happen. My dad had a boat come loose and pass him once. He was a smart guy who towed daily with his job at a salvage yard.

At least you weren't towing it behind this.....

Spotted today in Navarre beach FL.

You must be registered for see images attach
 

riotwarrior

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Sometimes bad things happen. My dad had a boat come loose and pass him once. He was a smart guy who towed daily with his job at a salvage yard.

At least you weren't towing it behind this.....

Spotted today in Navarre beach FL.

You must be registered for see images attach

I'd tow with that....maybe ....but it would be my 6x8 tip deck trailer for the six wheeler...:rotflmao and the six wheeler...that would be safe right guys? maybe 1200 lbs total???
 

FORDF250HDXLT

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I'd tow with that....maybe ....but it would be my 6x8 tip deck trailer for the six wheeler...:rotflmao and the six wheeler...that would be safe right guys? maybe 1200 lbs total???

no way.just something like a wood splitter....maybe lol.
 

laserjock

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I wouldn't put anything on it with any tongue weight at all. I had one of those and they are not all that sturdy. Maybe one of those luggage pod things but That would be about it.
 

79jasper

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I don't even get why lower class receivers are made.
Overkill. Go big or go home.
Also, I thought it was a big no no to twist safety chains? It lowers the work load rating of the chain. You go from pulling force to twist shear.

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stealth13777

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Interesting point. I'd still rather twist than drag it on the ground, especially when towing a trailer that isn't mine. But that makes really good sense.


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franklin2

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Do you guys put your chains in a "X", putting the pass side trailer chain on the driver's side of the truck hitch and the other one opposite? I don't know where people learn about such things, but I happen to find out about this idea word-of-mouth and wish I had been doing it since I started hauling. The "X" will cradle the trailer tongue if something bad happens and the trailer tongue drops.
 

Sycostang67

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I bought my first new trailer in 1999. The first one that I owned with a 2 5/16" ball. The dealer was tightening the ball onto the head and snapped the threaded shank of the ball. He wasn't that big of a guy and the wrench was not that long. It must have been defective. Other than that, I've never seen or heard of ball problems. Pintle is my preference now though.

I had a 2" ball snap on a 95 F-150 I used to have. I had the 2" receiver that bolts to the bumper which was a heavy custom job. I was pulling a single horse trailer(empty, thank goodness) along a dirt road and crossed one of those fake cattle crossing grids. It was made of rubber strips across the road to simulate the grid. It was windy and one of the strip flew up and hooked a stabilizing jack on the trailer and ripped the ball right off my stinger. Safety chains did there job and allowed the trailer to put a softball sized ding in my tailgate. I had a spare ball so I was back on the road rather quickly. That was the first and only time I have had that happen.
 

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