Why two hitch designs GN and fithwheel?

[dawall]

I do not see the advantage of a fithwheel hitch design? Why isn't everything a GN hitch?



Dan

 

[bmoeller]

The 5th wheel is easier to hook-up, since you can see it better. They can build the trailer a bit lighter. The goose puts more stress (leverage) on the framework on the front of the trailer, so it needs to beefed up. Could be wrong, but I don't think safety chains are required. The 5th uses a similar latch design as what the 18-wheelers use.



The goose does offer more movement for off-road, or steep drives. There are adapters to convert a trailer to be pulled with a gooseneck hitch, but not all trailers are strong enough to handle the stress.

 

[dawall]

Thanks for your reply. I bought a three horse trailer and they of course are all GN's or bumper pull. Just never thought to ask why there are two different setups for pulling RV trailers. You wouldn't think that engineering the trailer to run with a GN hitch would be all that costly or that much heavier that it would make hardly any difference in the price of the trailer. As to hooking up, my personal experience is that it is easy to hook up a GN by yourself. I do need to lift myself up out of the seat a bit though to see the ball. But I could see fithwheels would be easier because your looking right at the connection with out craning your neck much.

Dan

 

[DIESELMAN]

Lift up in the seat a little - Hah! I have a 100 Gallon Tank in the back of my truck, and when hitching the Gooseneck, I can't see squat. Not unless you stick your head out the rear window or get out and look. Being a dually, that sucks too.



Here's what I did. I painted a white stripe in the middle ridge of the bedliner and tailgate, and I put a small fisheye mirror on the curb side of the front of the trailer. I can now drop the tail gate, make sure the trailer is high enough, then back to the trailer using just the rearview miiror. The hitch will pass over the line and I can see the ball line up in the fisheye mirror from the rear view mirror. First Time, Every time.



Of course I hitched a million times before I did this little trailer bomb.

 

[LesStallings]

Regular cab, no tool box or tank - no problem seeing the GN.



Dieselman's fisheye should solve the problem for anyone with QC or box/tank. I may have to go that route if I get the below the rails combo tool box/tank.



Thanks for the tip.

 

[RustyJC]

If the gooseneck were a superior hitch design (it's not - the 5th wheel segregates the load carrying and drive functions), I imagine we'd see it on all the Class 8 semis out on the highway, and we certainly don't. The gooseneck's primary advantage is articulation in off-road applications such as agriculture, etc.



Rusty

 

[dawall]

If the gooseneck were a superior hitch design (it's not - the 5th wheel segregates the load carrying and drive functions), I imagine we'd see it on all the Class 8 semis out on the highway, and we certainly don't. The gooseneck's primary advantage is articulation in off-road applications such as agriculture, etc.



Rusty

Well you make a good point that GN's are not the hitch design used by semi's. From my perspective though(using GN for horse trailer) I just do not see any advantage to the fithwheel design that would make it compelling to use over the GN. It seems like the GN is more versatile.

So what do you mean that the fithwheel hitch separates the load carrying and driving function? Don't they both have about the the same percentage of pin weight?



Dan

 

[RustyJC]

So what do you mean that the fithwheel hitch separates the load carrying and driving function? Don't they both have about the the same percentage of pin weight?

Dan,



The 5th wheel carries its pin weight on a large (relatively speaking) load plate, so the unit loading (PSI) is much smaller than a gooseneck that carries its pin weight on a relatively small ball. The drive forces (acceleration and braking as well as steering) on a 5th wheel hitch are transmitted by the jaws of the hitch to the kingpin of the trailer. That's what I meant by separating the load carrying and drive functions. The gooseneck has to absorb/transmit all these loads (i. e. , pin load and drive forces) through the ball.



As a point of interest, one might want to check the state laws to see what they say about allowing passengers to ride in a trailer. Although I'd never do this, the laws are interesting in that almost all states that do allow passengers in a trailer only permit this in a trailer with a 5th wheel-type (i. e. , positive) coupling device, and 5th wheel trailers aren't required to utilize safety chains as well.



For your horse trailer application, there's nothing at all wrong with the gooseneck design. As I said in my previous post:

The gooseneck's primary advantage is articulation in off-road applications such as agriculture, etc.

(By the way, in a sense I ain't got no dog in this fight - see my signature. My B&W system means I have a gooseneck and a 5th wheel hitch. My intent isn't to trash the gooseneck hitch, but rather to address your question in this thread's original post when you said that you didn't understand the reason for a 5th wheel hitch design. )



Rusty

 

[Don-T]

I think Rusty is saying the fifth wheel carries the weight on the plate the trailer sits on, and that is a much larger area than the top half of the GN ball. The fifth wheel pin is used to carry the pulling / stopping and lateral force. I would think the fifth wheel hitch is more secure and will last longer than the GN ball and would hold much larger loads.



A trailer with a fifth wheel pin should have much less stress on the frame than a GN hitch would and would be stronger and last longer than a GN hitch.

 

[dawall]

So if I understand it right, the advantages of 5th wheel hitch:

Higher load carrying potential, more even transmission of load forces to the trailer, easier hitch hookup without aids



And disadvantages:

limited articulation, large hitch assembly in the bed, maybe cost



Dan

 

[SRadke]

So if I understand it right, the advantages of 5th wheel hitch:

Higher load carrying potential, more even transmission of load forces to the trailer, easier hitch hookup without aids.



And disadvantages:

limited articulation, large hitch assembly in the bed, maybe cost



Dan

This is right on. You'll find fifth wheel trailers require your truck to be within a few inches of the right height to even be able to tow them, not so with the goosneck. This all goes back to the articulation issue mentioned earlier. Also, the structure required by the goosneck's neck design also demands more weight in the trailer as well as leaving less room above the neck where space is at a premium in a RV.



-Scott

 

[MCherry]

I don't agree with the comment about fifth wheel being a more secure hitch.



If you read some of the RV webiste forums, you'll see items about people who thought their trailer was properly hitched, with the latching mechanism closed, and found it was not when they drove away. It drops the travel trailer on the bed of the pickup, often damaging the sides of bed and maybe the trailer as well. I"ve read one or two posts where that didn't happen right away, only after some travel.



With a gooseneck, it's obvious whether the hitch is on the ball or not. If you don't close the latch, I guess its possible it might jump off while travelling, but even that seems unlikely since such a large part of the weight of the trailer is carried by the truck.



It's probably true that its more desirable to have the load spread over the hitch plate, and having a wide plate may also cut down on the trailer leaning if you go over uneven surfaces like a driveway entrance, etc.



Plusses and minuses for each kind, I guess.

 

[RustyJC]

I don't agree with the comment about fifth wheel being a more secure hitch.

You can agree or disagree, but that doesn't change the fact that the regulatory authorities consider the 5th wheel's positive jaw/pin design more secure than any ball hitch, including a gooseneck. That's why some of them allow passengers in 5th wheel trailers, and none of them require safety chains with 5th wheel trailers.



Rusty

 

[Jonesey]

Sorry to be late in the debate, but here is what I will be doing. I have a fifth wheel camper, and I will be doing away with the hitch that mounts in the bed. I want an adapter for the kingpin and a gooseball in the bed. Gooseballs are rated to carry more weight and take less room in the bed.

As far as big trucks having 5th wheels, that is so you can back up under them and take off (only yard trucks do that) The fifth wheels on big trucks and the ones in our pick-ups are an entirely different story. (I drive a big truck for a living) As far as vacationing and pulling campers I would recommend a goose ball in the bed, and an adapter for the kingpin of your fifth wheel.



Chris

 

[RustyJC]

That's an extremely ill advised idea. If you'll do a search for "gooseneck adapter" on this forum as well as RV forums such as iRV2.com, you'll find that the gooseneck adapters can pull the pinbox out of the 5th wheel frames. This is because the 5th wheel frame is not designed to handle the additional moments (torque forces) produced by the gooseneck adapter. This is not just a theoretical possibility - a number of individuals on these forums have damaged their 5th wheel RVs by using these adapters.



If you want a gooseneck hitch, a proper 5th wheel hitch to tow your RV and a clean bed when neither is in use, I would suggest theB&W turnoverball gooseneck with their companion 5th wheel hitch.



Rusty

 

[David Oxland]

I was alwas under the impression that the important thing about a 5th was that the point of loading and thrust (during braking) was over or just ahead of the aft wheels. It's a consideration in handling and braking.

If you are braking and cornering on slippery surface and the point of load is aft of the wheels it encourages tendency to jack knife.

Also when applying the load aft of the wheels it makes moment about the axle to take weight off of the front end.

 

[J&LRam]

some 5er manufactors do not recommend a goose neck adpter for their units. Check with them first. Be sure to use safety chains with GN. The first time I poped a ball loose was angling across a ditch with a 24ft stock trailer. The second time was with a 32ft stock trailer that had safety chains hooked. Big difference.

A 5er hitch will not come unhooked if hitcked properly... ..... JIM