Another Andersen question

[CaptnJohn]

You might ask Anderson if they ever paid a claim on that warranty.

[Sdgood1]

I bought the B&W patriot 18K slider. I use the slide every time I go to park it.The 5 seconds it takes to do this, just means I don't have to worry about hitting. NO problem hooking up at angles as of yet.

[dlleno]

Originally Posted by CaptnJohn

You might ask Anderson if they ever paid a claim on that warranty.

It's actually out of Andersen's hands. It appears to me that The $ come from a separate insurance company and settlements are subject to arbitration. It's more of a marketing tool than a mechanism of protection just my opinion .

[Theunz]

Dlleno, you're making a mountain out of a mole hill. It's like the "towing with a 3/4 ton" debate, thousands are doing both with out any problems but someone is always saying what if. Do a search on the various RV forums and see how many have had a frame failure directly attributed to the Andersen hitch, and if any compare that to those from conventional hitches. I think you'll find it works out in Andersens favor.

[dlleno]

I'll own up to drilling down deeper into details than necessary on occasion. but even with that disclaimer I agree with your point because even the details themselves (extending the pinbox by 3") cannot (imho) not by itself cause frame breakage. A well-built frame will tolerate this well, I claim, and it won't even care that it (the extender) is there. So what I should be saying is that you will loose the warranty argument if it does. I'm also saying that if the frame breaks it won't be because of the Andersen adapter (as a matter of engineering) it will be because the frame wasn't welded right or some other reason -- but that you will be out of luck because you took the warranty out of the mgfs hands by extending the pin box 3". I would also offer that the reason frames aren't breaking and Andersen isn't paying for them is because the modification is very small and within the tolerances built into the frame by the mfg - my argument is about who is taking warranty ownership. As we say in the diesel power modification world, "you become your own warranty station". A great many trucks (a previous one of mine included) have been modified outside of factory limits and still keep on going like the energizer bunny.

the mountain I made that is really a mole hill is probably about the offset -- a 4" offset (pin behind the axle) with a long wheelbase 3500 diesel SWR truck will probably go un-noticed (Ram mega cabs have a long wheel base. they are not that much shorter than a crew cab long box). Will a 60mpg wind gust steer your truck? probably a little, but with winds that high you have bigger problems.

So what appears to be me over analyzing (which I admit to doing) is really me going into the details to understand them, so I can then step back to understand how important they are. I appreciate the patience of this group over that journey.

I would only add that, as regards towing with a 3/4 ton truck, well I am quite allergic to overloading which is very easy to do with a 2500 and a fifth wheel (going over GVWR) and not well advised imho because it increases risk. it doesn't cause accidents -- it increases the risk of getting into one, and increases the severity of accidents if you are in one, and also puts more ammunition into the hands of other parties who might come at you for legal partial responsibility if your pin weight causes you to exceed your vehicle's weight ratings.

[QKnot]

Oh for Pete's sake.

By their very design, rail 5th wheel hitches distribute the weight across the bed. The Andersen does the same. Yes, it attaches to the goose ball (so does the B & W Companion). However, the way the Andersen is torqued actually pulls UP on the ball. It's only there to keep the hitch in place; it's not applying the load on the ball, ahead of the ball, behind the ball, etc. The actual weight of the 5'er is distributed down through the 4 legs and across the bed just like having a conventional rail hitch. You can adapt an Andersen for use with rails, by the way.

You can argue all you want about the effect of the Andersen adapter on the pin box. But the load on the truck, long bed or short bed, is not a point load. It's distributed.

BTW I'm using mine with a Ram 3500 SB and so far have no issues turning.

[dlleno]

Thats like saying the drivers weight is evenly distributed axross the frame because the seat is bolted down and screw threads pull up. The pin load is applied at a single point. Of course that weight is distributed via the andersen frame to the bed but that doenst move the weight forward of its point of application. There is still a moment or lever arm created and its value is equal to pin weight times the offset distance, and there is no moment applied anywhere in the opposite direction to counter it.

[QKnot]

Your analogy about the seat fails to take into account the rails at the bottom of the seat.

And I stand by my statement. The thing is basically a pyramid and puts no point load on the truck unlike a gooseneck trailer. It's torqued to the bed which is torqued to the frame and acts like a composite system. The counter is the front suspension of the truck itself when braking and the weight of the front axle when accelerating.

[KIEHLS]

Structural Designer here...when torqueing up on the gooseneck ball you are applying more force to the ball statically (in tension) than it will ever see dynamically. The forces from towing are distributed thru the pyramid frame and into the bed frame over that large footprint. I have had no issues with my Anderson (two years of moving every two weeks) but I went with the steel unit. Not sure how the aluminum performs over time due to alum and weld fatigue issues but I can assure you that Anderson is not in the business of under engineering and then manufacturing a product that has a high likely hood of causing death if it fails.

[KIEHLS]

and there is no moment applied anywhere in the opposite direction to counter it.[/QUOTE]

if that were true you would obviously and quickly have a failure; the fact that it sets there and does not fail anything means there is an equal and opposite reaction.

[dlleno]

First of all, its good to remember that no one is saying there are engineering weaknesses in the Andersen system. What I am saying is that there is nothing inherent in the Andersen system that is capable of moving the nominal load application point forward of where is actually is applied, which is 5-ish inches behind the ball. This is an Engineering statics question not a dynamics question. its neither bad nor good; it just is. There is a lot of techno-babble surrounding this (Andersen) system and I dont' know where it comes from, but it is certainly mis-leading.

secondly, yes all traditional hitches utilize the bed for a larger footprint, and many of them (B&W included) allow for re-positioning of the pin weight with respect to the rear axle. only they dont' lie about it. B&W, for example, makes it very clear that moving their adjustment arms aft moves the load point aft by the same amount, and there is no claims of using rails or other structures to change the nominal application of the pin weight.

Originally Posted by QKnot

Your analogy about the seat fails to take into account the rails at the bottom of the seat.

I suspect Andersen may be causing folks to confuse the concept of "distributing weight across a larger area" with that of "re-distributing weight to a new (average) location". The seat analogy is exactly my point: just because the rails are bolted down doesn't mean they (the rails) re-distribute weight. torque the bolts down as tight as you want -- the seat (and your body in it) still applies weight downward wherever the seat is, as far as the axles are concerned.

The thing is basically a pyramid and puts no point load on the truck unlike a gooseneck trailer.

the axles don't see the gooseneck as a point load, and neither do they care if the nominal load point is in the bed or 18" higher than the bed. Its interesting to note that the pyramid introduces new lever forces due to this additional height, but that is a subject for another day.

The pyramid magic that Andersen as deployed here lies in the strength of the structure that raises the point load several inches above the bed. it has nothing to do with re-distributing weight across the two axles by utilizing the bed. you don't want pin weight in your bed anyway (that material is sheet metal) you want it applied to the frame. Just because the weight of the pin is spread out across the base of the pyramid doesn't move the load point which is still offset behind the ball. yes the bed does see weight -- I'm not saying otherwise. I'm saying utilization of the bed provides no magic for re-distributing weight

[quote]
It's torqued to the bed
[/quote

Certainly, you apply torque to a fastener that pulls up on the ball, forcing the pyramid down onto the bed, but this applies no torque to the ball, the bed, or the pyramid.

... which is torqued to the frame and acts like a composite system.

Its true that all those parts are bolted together but doing so does not re-distribute weight applied from a certain point at the top of the structure. otherwise, cherry pickers and cranes would never tip over.

the counter is the front suspension of the truck itself when braking and the weight of the front axle when accelerating.

The dynamics of the front suspension (or the rear suspension for that matter) has nothing to do with the the nominal placement of weight behind the gooseneck ball.

[dlleno]

Originally Posted by KIEHLS

if that were true you would obviously and quickly have a failure; the fact that it sets there and does not fail anything means there is an equal and opposite reaction.

you are right but I didn't state my point well. let me clarify -- what I mean here is that within the pyramid itself, or its application of weight to the bed, there is no moment applied anywhere that is opposite to that created by locating the pin behind the ball, so as to re-locate the load point forward of where it really is. As for the larger system of the truck itself -- yes of course the very weight on the front axle is what provides the opposite moment so that the sum of the moments is zero. otherwise the truck would do a wheelie. BTW this analysis (the wheelie) applies ONLY when the resultant Andersen offset locates the pin BEHIND the axle.

Again I'm just saying there is no magic. put the Anderson's offset in front of or on the axle (majority of trucks) and you have a beautiful system. Well its beautiful even when behind the axle because its such a small amount.

[KIEHLS]

Originally Posted by dlleno

you are right but I didn't state my point well. let me clarify -- what I mean here is that within the pyramid itself, or its application of weight to the bed, there is no moment applied anywhere that is opposite to that created by locating the pin behind the ball, so as to re-locate the load point forward of where it really is. As for the larger system of the truck itself -- yes of course the very weight on the front axle is what provides the opposite moment so that the sum of the moments is zero. otherwise the truck would do a wheelie. BTW this analysis (the wheelie) applies ONLY when the resultant Andersen offset locates the pin BEHIND the axle.

Again I'm just saying there is no magic. put the Anderson's offset in front of or on the axle (majority of trucks) and you have a beautiful system. Well its beautiful even when behind the axle because its such a small amount.

I think I may have stumbled upon your concern...the point load is behind the drive axle thereby 'lightening' the steering axle. 1) I believe the hitch does distribute some of the load in front of the drive axle...the four tubes at the corner transfer load to the base which transfers it thru every fastener in the bed to the frame, etc.
2) for simplicity if we assume a point load 125mm (5in) behind the drive axle of a 3000mm wheel base truck then a 4000# load would equate to 4167# on drive axle and negative 167# on front axle?

[dlleno]

Originally Posted by KIEHLS

I think I may have stumbled upon your concern...the point load is behind the drive axle thereby 'lightening' the steering axle. 1) I believe the hitch does distribute some of the load in front of the drive axle...the four tubes at the corner transfer load to the base which transfers it thru every fastener in the bed to the frame, etc.
2) for simplicity if we assume a point load 125mm (5in) behind the drive axle of a 3000mm wheel base truck then a 4000# load would equate to 4167# on drive axle and negative 167# on front axle?

exactly! while that isn't really a "concern" per se its a physics truth that is really very simple and I'm surprised that it is so confusing. I don't get the motivation to construct a story that weight is distributed differently when the pyramid is in place.

I'm interested in more of your thinking re: (1) above. to be sure, the pin weight is spread out over the pyramid's understructure footprint, which is to say that you wouldn't want to put your finger under the pyramid's front side to test how much of the pin weight is there. but its also true that the frame cross members and other structures do that themselves anyway, even for a gooseneck trailer if ball itself were located in same place. so while I agree that I'm not going to put my finger under the pyramid, I'm also saying that the average distribution of the load has not changed by virtue of the pyramid's existence, and that the axles see exactly the same weight proportions as if the pin were resting directly on the bed exactly the same distance from the ball as the Pyramid places it. In other words, if the Andersen installation results in the geometries you outline (pin behind the axle) the moments would sum exactly the way you calculated.

put another way -- if a truck's Andersen installation is truly "pin behind the axle", then an accurate and honest trip to the scales would prove it -- if one weighs before and after hooking up the trailer, I claim the "after" measurement would show that the front axle actually would weigh LESS than before the trailer was loaded. of course, the difference might be less than the resolution and measurement repeatability of the scale, and we are talking about very small numbers here that might not be detected.

In short, I suggest (and want to challenge) that you can model the Anderson (and any other rail-based or picture-frame based hitch system that puts a structure under the pin) as a single point of weight application in a Static system where the moments (about the Truck's axles) sum to zero.

[dlleno]

I would like to make some additional clarifications. The Andersen DOES transfer weight to the bed material itself, as witnessed by reports of deflection. So imho this (the bed floor) appears to be the primary mechanism by which weight is distrubuted to the frame. (This point is solved by pullrite as they supply a puck mounted flavor of their own similar hitch). I would still point out however that the footprint of the pyramid base cannot possibly transfer weight forward of its application point. You can make the pyramid base fill the entire bed, to all four corners , and the axles and tires would not know or care or see any difference in weight.

With apologies for going on and on here... think about applying a load to the basket of a cherry picker: the structure of the arm and the vehicle cannot transfer any weight from the basket (or else it could never tip over). The weight in the basket creates a moment arm that must be equaled via ballast weight or extended stabilizing feet.

So all Im emphasizing is that there is no magic in the pyramid.


Also...After further reading and comparing with my own experience and research i will point out that andersen is legally protected from anything any of their staff says verbally. That explains the differences in stories heard around the circle and why some of them don't make engineering sense, and why their written responses and faq's on this topic are rather vague .

[Theunz]

WOW!!... All this mumbo jumbo physics talk about the Andersen hitch has made me decide to throw mine in the dumpster. Too bad, as it's been the smoothest, quietest hitch I've ever used. The ease of taking it in and out may however be making my back and arms weaker. I think I'll just get one of those heavy clunky monstrositys again. NOT!

[KIEHLS]

the evidence...
Chevy 3500 LB DRW
2017 3791RD


steer 4880
drive 3700
trailer 0


steer 4800
drive 7520
trailer 12460

[woodman]

I have a 2017 F-350 Diesel SWR and shortbox with Pullrite auto slider. Over 35K miles and 6 yrs and no incidences. Auto slider is not difficult to hook up and you never have to worry about turning. Simple mechanics apply to hook up or unhook. I use my truck half the year pulling our 5th and the other for my business. Long beds and dually’s are obnoxiously big, cumbersome and wouldn’t work for my business. I had a shortbed 2011 F-350 that had brackets mounted to the frame for the Pullrite. With the new 2017 F-350, I have a OEM puc system that works slick and makes it easy to install and remove the hitch. Idk about you, but I want to travel freely and get equipment that has the best chance of avoiding problems, so I apply that strategy to wheels, tires, brakes and and everything else. Pullrite was hands down the best solution for a slider. Demco makes a nice slider too, but has other fiddling adjustments and doesn’t have the resale value.

[StageCoachDriver]

Not being a goose-neck person, my guess is so the hitch is that way so it will work in a 6.5 ft bed.

[bshgto]

Originally Posted by Theunz

WOW!!... All this mumbo jumbo physics talk about the Andersen hitch has made me decide to throw mine in the dumpster. Too bad, as it's been the smoothest, quietest hitch I've ever used. The ease of taking it in and out may however be making my back and arms weaker. I think I'll just get one of those heavy clunky monstrositys again. NOT!

To the OP, Just buy this hitch, you won`t have to put up with people that don`t have a clue what they are talking about. My hitch gets bashed and talked about on multi-able Forums with no real conclusions but this one you never hear anything about but it`s the same thing same benefits.

https://www.youtube.com/watch?v=wwk49iH78-Qhttp://

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