Another Andersen question

[dlleno]

Hi all,

I'm the analytical type, prone to dig well into details and much research before I buy. Believe it or not I have not found an answer to the below:

According to the following drawing, the link to which Andersen pushed to me over email , the Andersen hitch (3220) structure itself moves the application of weight 5.375 inches to the rear of the gooseneck ball. that is, wherever your gooseneck ball is, the pin weight will be applied 5.375 inches to the rear of it.

http://www.mediafire.com/file/nbzl01...dimensions.pdf

So -- no matter how you orient the Andersen kingpin adapter (where the funnel is), the fifthwheel's pin weight is going to be applied 5.375" to the rear of the gooseneck. this seems like a simple Engineering Statics question: what am I missing?

the question behind the question is -- why would you want to apply the kingpin weight to a point 5 inches behind your gooseneck? Or are most gooseneck balls mounted forward of the rear axle by more than 5 inches? My 2018 RAM puck system locates the gooseneck ball directly over my rear axle, or maybe 1 inch forward, as near as I can tell, so the way I read this information, the Andersen hitch introduces a 5-inch lever between the Axle and the kingpin on my truck.

Due to the popularity of this hitch I must be missing something. surely all the Andersen hitches out there are not applying kingpin weight behind the axle?

[DQDick]

Pullrite has a similar product, you may want to compare them both before you buy. Pullrite will be at the National Rally if you are going.

[jsb5717]

I have the turnover ball so I have the version that connects to that. Yes, the Andersen Ball is 5" to the rear of the turn over ball. According to Andersen, though, the design of the hitch distributes the weight so that it is still over the axle (or over the turnover ball which should be over the axle if installed correctly). But with a short box truck the added 5" set back is helpful in sharp turns. This is less critical with a long bed truck. My kingpin coupler is forward of the pin so when towing the trailer sits 9" further back. This is beneficial for allowing more room between the tailgate and the trailer.

I can tell you that my trailer tows smoothly and quietly. I love the setup.

[dlleno]

Originally Posted by jsb5717

... According to Andersen, though, the design of the hitch distributes the weight so that it is still over the axle (or over the turnover ball which should be over the axle if installed correctly).

I would like a currently practicing mechanical engineer to respond to this (I left the EE field many years ago). That aside my reaction to this is that this statement is complete nonsense, and that any 2nd-year engineering student taking a Statics class would see right through this smoke. Unless they have pre-stressed the cross members, (or the gooseneck ball itself ,which is a horrifying thought) there is no amount of sales talk that can move the ball mount forward of where they place it! its just simple engineering mechanics.

I like the Andersen concept; I just can't come to terms with the deceptions as of yet anyway

[jsb5717]

I'm not an engineer, just a logical thinker. There is a substantial base to this unit that is torqued to the bed via the turn over ball so there is a pretty good amount of weight distribution going on.

My experience is hands on and positive. Is it possible you're overthinking where the point of weight is impacting the truck bed? I don't think there are deceptions, there's just not a lot of overly detailed engineering specs out there that most of us wouldn't understand anyway. It sounds like you can understand the more technical specs and I do understand needing to feel comfortable with the direction you choose. Are you able to find that level of detail in other hitches you've researched?

All I know is that it works as advertised. One of the reasons I chose this hitch is because of the 5" set back.

[CaptnJohn]

Originally Posted by dlleno

I would like a currently practicing mechanical engineer to respond to this (I left the EE field many years ago). That aside my reaction to this is that this statement is complete nonsense, and that any 2nd-year engineering student taking a Statics class would see right through this smoke. Unless they have pre-stressed the cross members, (or the gooseneck ball itself ,which is a horrifying thought) there is no amount of sales talk that can move the ball mount forward of where they place it! its just simple engineering mechanics.

I like the Andersen concept; I just can't come to terms with the deceptions as of yet anyway

Too much hype for me as well. There is a thread today here or FR site where a Ram SB and 5er kissed with the Anderson set back. On my SB I stayed with a slider. Only needed 3 times but it was there when Anderson would have not helped.

[dlleno]

The consequences of locating the pin behind the axle are probably noticable only in extreme circumstances. So i expect that Andersen is working beautifully as regards the towing experience. What i don't get is why locating the pin 5" behind the axle is an acceptable main stream best practice

I also find the pin extender solution (rotating the kingpin adapter) mildly disturbing because any time you increase the distance from frame to pin, while keeping pin weight the same, this puts additional lever stress onto the frame. And multiple incantations of the Magnuson–Moss Warranty Act wil not change the fact that the andersen modifies the original design intentions of the frame mfg.

Im interested in your slider exoerience . Do you find the need for the likes of a pullrite?

[DQDick]

We have had a pullrite slider for most of our towing experience (over 80K) needed it bad twice both unusual situations that many wouldn't even try. Have been glad I had it even in tight service station situations.

[PNW Fireguy]

OMG...then just don’t buy it!

[dlleno]

Since my shortbed locates the gooseneck directly over the axle that's likely the best approach for me, as id rather not let the trailer have that leverage to steer my truck. But a longbed with the gooseneck ball forward of the axle, flip the kingpin adapter around so youre not stressing the frame by extending the pinbox, and i think the outcome would be different.

[Last2Die]

I called and spoke with Mr. Anderson. I have a long bed and asked him what way the hitch should face. He told me with a short bed you only have 1 option, the long section of the hitch facing the cab, with a long bed you can go either way. I have the long section facing the tailgate, the ball sits about 2inches in from of the rear axle. If your that concerned maybe get a standard hitch, technology is not for everyone, some like the tried and proven and dont venture far from that

[dlleno]

Indeed . That makes sense. Bummer if i had a long bed it would work. Too bad for me the concept is great; just not for short beds unless one is comfortable with the offset.

For the record, it has nothing to do with technology . Its just physics

[Last2Die]

If you want to understand the “physics “ behind how and why, and where the load sits why not just call Anderson and ask them. I’m sure they can answer your questions better then we can, considering my degree is in CS, and not engineering.

[dlleno]

Thats good advice and yes I have talked to both Andersen and Pullrite, who makes the same type of hitch with a few modifications I assume to avoid patent infringement.

I find that Pullrite is very open and honest about these matters while Andersen obfuscates the technical detail and attempts (at least in their communications with me) to make short bed owners feel like they are locating the pin weight over the rear axle when they are not. So yes my trust in Andersen is shaken because of this; I am less inclined to believe them because they tried to deceive me and I won't have any of it. If I end up getting this kind of a hitch it will be a pullrite and not an Andersen.

But all of that aside, once we understand that the pin is applied aft of the axle the question is "why is that so horrible?". Since yesterday I have begun to think about this issue differently. To be sure, when there is room (such as in a long bed) one should always locate the pin at or forward of the axle. But shortbed owners do not have the luxury: we have to look at all of the available solutions and assess all of the trade-offs (including this one) against the benefits. Here's an inventory of the options for short bed owners - let me me know what is missing

1. do nothing: (get a conventional hitch) and live with the cab clearance issue. thats not a good choice imho

2. adjust a conventional hitch (such as a B&W) to locate the pin behind the axle. this gives a little room but not as much as an Andersen. you get a little more cab clearance and create a very small lever for the trailer to steer the truck.

3. get a manual slider. optimizes highway driving by locating the pin where it should be, but adds the inconvenience of having to operate the manual slider and to know when to do so.

4. get an auto slider. optimizes cab clearance, eliminates the inconvenience of a manual slider, but makes it harder to hitch up (restricted hitching angles)

5. get a Pullrite or Andersen. these guys locate the pin further behind the axle but give you additional clearance and are the easiest to hitch up especially at angles or uneven ground.

I have to admit that once I laid out the options as above, the hitching benefits of the Andersen/Pullrite are attractive. To be sure, if one could guarantee near-flat surfaces and straight-on hitch angles, the auto-sliders are best hands down. but if you're willing to give up on the cab clearance benefit of the auto-slider, the newer unconventional hitches from Andersen and Pullrite are very compelling with a very small disadvantage in the form of sway control which, with late model trucks that are not overloaded, may in fact be a moot point.

[CaptnJohn]

You forgot the cost of auto-sliding hitches. I thought about one years ago and went with the B&W slider instead. It is now going on my 3rd truck and used with my 4th 5er.
Yes, some sliders can be particular when hitching, my friend has a Curt he mumbles about. If the trailer came off my B&W it goes back on easily at any angle.
You will know when you need to pull the lever. I have needed it only 3 times. Very simple, just pull the lever with the trailer brakes on.
Dropping a ball is no more easily done than riding the trailer onto the hitch.
On this forum recently it was stated a frame problem was denied by Montana and Lippert due to use of the Anderson. Anderson also denied the claim ~ where is that guarantee?

[dlleno]

I did leave out the cost of the auto-sliders you're right about that. I'm glad to hear from a manual slider guy too. good to know that they are not as horrible as others say!

I also neglected to bring forward my previous concern about trailer frames warranty. these devices that effectively lengthen the pin box, in my opinion, are going to loose the argument with the frame mfg no matter how many times they quote from the Magnuson–Moss Warranty Act, because the actually change the design intentions of the frame by increasing the pin box lever stresses.

[dlleno]

V2 Options and tradeoffs for short bed hitches

1. do nothing: (get a conventional hitch) and live with the cab clearance issue. thats not a good choice imho.

2. adjust a conventional hitch (such as a B&W) to locate the pin behind the axle. this gives a little room but not as much as an Andersen. you get a little more cab clearance and create a very small lever for the trailer to steer the truck.

3. get a manual slider. optimizes highway driving by locating the pin where it should be, adds the inconvenience of having to operate the manual slider (pull lever with trailer brakes on) and to know when to do so . most cost effective while preserving the pin weight location. usually rarely used but good insurance.

4. get an auto slider. optimizes cab clearance, eliminates the inconvenience of a manual slider, but makes it harder to hitch up (restricted hitching angles). expensive

5. get an Andersen. many prefer the hitch-up process at angles or uneven ground. very lightweight and can be removed easily. may or may not solve the cab clearance problem. introduces questions about trailer frame warranty , due to extending the pin box via kingpin adapter. locates the pin up to 5.375" behind the axle. Pullrite makes an equivalent hitch with a choice of 3.5" or 4.5" offset plus an additional 4" at the kingpin adapter.

[jsb5717]

Just learned something new. I saw on Andersen's site a comment about the turn-over ball being mounted 5" in front of the axle. I checked mine and sure enough...it's at least 5" forward. That means that Andersen's hitch places their ball directly over the axle and the weight is distributed over the cross members between the truck frames.

I've never felt like the trailer is steering the truck. As long as the truck is adequately spec'd for the weight of the trailer you're towing and the pin height allows for fairly level travel it will feel great and secure. That's been my experience.

BTW...I've towed 5er's with short beds for over 20 years with no issues. I prefer the shorter wheel base and pay attention in the tight turns.

[waynemoore]

Agree with Darrylwt. The one item dlleno left out is get a long bed truck and no more problem.

Good gref guys this is not rocket science at least to me.

1 short bed trucks are convent to park and get in small garages. But cause all kinds of problems when hitched to a fiver.

2 long bed trucks are a bit more of a pain to park and will not fit in a car garage. But are great for towing a fiver or for that matter all kinds of towing.

So in my opinion a short bed truck is for running around town and taking stuff to the dump. The F150 or the 1500s work just fine for this.

If you want to haul these heavy fifth wheels you need a long bed truck one ton SRW or DRW. They are long enough to provide stability when towing and allow for proper placement of the hitch.

Just my opinion is all.

[dlleno]

Thanks guys yes I did mean to make it clear that the 5.375" offset "behind the rear axle" is for MY truck ,where the OE puck locates the gooseneck over the rear axle. long beds are a different story and my issue with Andersen is not that the 5.375" offset was a bad idea; just that the truth of the matter was obfuscated as it relates to MY truck. I find it is commonplace to find true gooseneck balls mounted forward of the rear axle (I've not seen a true gooseneck trailer pulled by a short bed) which places a small portion of the weight onto the TV front axle. So moving the pin back to the axle is not that bad of an idea. its a curious one, but not a bad one.


jsb5717 your experience makes perfect sense. the Andersen is only .375" aft of your axle which is, for all practical purposes, directly over the axle and your trailer won't steer your truck because there is no leverage to do so. My argument on that subject is that if the pin is really 5.375" behind the axle -- as in my truck -- that is greater than the most radical adjustment of a B&W fixed companion hitch and raises a flag because now there is a small lever available to the trailer to steer the truck because the trailer is pushing 5.375" behind the axle and wagging the front of the truck. is that, in actual practice, problematic? That may be up for debate, except perhaps in extreme wind for example, and an overloaded (or nearly so) truck. the previous comments about not exceeding the trucks weight ratings are spot on, of course.

So with the exception of Ram short bed pucks, I'm sure there are a great many trucks, especially long beds, for which the Andersen does not commit this error and would be a manifestly cool solution. maybe I should trade in for a long bed...

So I certainly agree that the solution is a long bed.... and must also admit to some degree of thread drift here in that this was originally an Andersen thread and not a short bed thread. sorry for that.

the lessons learned re: Andersen is just to make sure you understand where the pin weight is located on your truck, and be prepared to loose the warranty argument with the trailer frame mfg when they find out that you have the capability to extend the pin box beyond the original design intentions via the the kingpin adapter . The solution to that, of course, is to flip the adapter around so that it *shortens* the pin box (moves trailer closer to cab) instead of lengthening it. If it were me I wouldn't do any of this during the frame's warranty phase because you will still loose the argument with the trailer frame mfg because you won't be able to prove that it was never flipped the other way. but after the warranty is over, the Anderson adapter will would actually reduce the stresses on the trailer frame by some very small amount.

and btw yes for the record I have read Andersen's verbiage regarding frame warranty. my reaction is that it protects them more than it protects you. I'd like a practicing mechanical engineer to weigh in here, but as I see it there is no free lunch -- you can't extend the pinbox (via the adapter) without introducing a greater moment arm stress to the frame, and there is no way to contort Magnuson-Moss to cover such modifications.

In fact, the very existence of Andersen's own warranty should be proof enough that the trailer frame mfg can and may deny warranty. And even if one got into a situation where they had to rely on the Anderson warranty I'm afraid that one is as tight as drum head, and appears to have been written by a very competent attorney.