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RJHILL

Changing out the STD 5th wheel ????

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Changing to the STD 5th for a smaller with air bags one doesn't make a lot sense.  The problem isn't a rigid 5th wheel plate it's the stiff rear suspension designed for heavy commercial loads .   Putting a band aid with a very expensive light duty (compared to STD) after market 5th wheel on airbags isn't addressing the problem.  The correct and by far less expense method would be to put the correct spring rate in the leafs for the lighter loads and add better shocks to control the compression and rebound of the axles.  Added bonuses would be your HDT would ride like a Cadillac, be far more safer (better road contact) and think about all the money you would save not having all your fillings jarred out.     

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That still doesn't account for the lack of side to side articulation on "most" 5th wheels.     The frame of a tractor is far stiffer in roll than a pick up, you can soften up the suspension and still twist an RV frame.     There are "some" RV's that can tolerate being towed by a standard 5th wheel, over time even they will likely show stress in the gooseneck area.   

Another consideration with RV towing, many tow with the hitch mounted well behind the axles, that alone amplifies every bump and jolt regardless of how soft the suspension is.     In the end, it IS your choice to use an air ride hitch, soften the suspension or, any other method that is safe to tow YOUR trailer.      If you tow with the 5th wheel right over the axle of a single axle tractor with a heavy pin 5K+ you may be OK on flat ground.     The frame will still twist going up a driveway, as the truck turns and goes up, the trailer will try to follow the fixed 5th wheel plate.

 

Steve    

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The issue is not one hitch is better than the other.  Both types of hitches are good and have their purpose.  The issue is really the lack of side to side articulation of the standard HDT 5th wheel hitch.  Because there is no side to side articulation there can be extreme twisting forces exerted on the 5er when turning through dips in the road, up and down driveways, etc.  These twisting forces would not be solved by changing the HDT suspension.  The standard 5th wheel hitch on an HDT would function fine if all you ever towed on was level ground and never had to turn into a dip or go up or down a driveway at an angle, or etc.

Additionally, the air bags common in the air hitches used by most HDT RV toters compensate for the rough/stiff suspension of an HDT.  They help smooth out the ride the trailer “feels”.  For some of the less robustly built 5ers this is a must (in my opinion), but some of the better built ones could survive without it.

What none of the 5ers built today will survive over the long term is the lack of side to side articulation in the hitch.  Some get away with it by being careful, but it is a risk I would not be willing to take with my “home”.

 

On edit, Steve typed faster than me, but expressed the same basic principle and added the benefits of hitch position gained by going with an RV hitch at the back of the frame (behind the HDT rear axle).

Edited by Chad Heiser

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What Chad and Steve said.

The other issue is that you want your truck to ride at the correct height, no matter what your pin weight is, and that is what the suspension of the truck will do.  You cannot lower the pressure in the air bags and expect to hit the correct height.  Maybe you can put different rated air bags in there expecting them to allow a softer ride, but you will still need the same amount of air to lift the rear of the truck, plus the weight of the pin of your trailer.

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RJHills comments are probably coming out of the HDT group of Facebook.  There is a large group there that are pulling with commercial hitches and claiming to have no issues.  At this year's National rally in Hutchinson, there was a 2009 DRV with a failed pin box and frame that had been towed with an MDT and solid hitch.

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He never once said the word "hitch" in that jumble of run on sentences. Changing the springs and shocks on a HDT and using a commercial hitch while hoping for a "Cadillac" ride rather than using an RV hitch with airbags is the silliest thing I've heard of here. Having read some of the comments on the Facebook pages I can believe what Jim says.

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3 minutes ago, Steve from SoCal said:

The more I hear about facebook, twitter et al , the happier I am I never got started

 

Steve

LOL, they have some scary posts on the HDT Facebook pages, Steve. And a lot of wrong advice.

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16 minutes ago, Steve from SoCal said:

The more I hear about facebook, twitter et al , the happier I am I never got started

 

Steve

 

11 minutes ago, Big5er said:

LOL, they have some scary posts on the HDT Facebook pages, Steve. And a lot of wrong advice.

Since Alie doesn't buy the Enquirer or Star anymore, I gotta have something to read while I'm on the crapper.... Facebook works....

 

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9 hours ago, Steve from SoCal said:

The more I hear about facebook, twitter et al , the happier I am I never got started

 

Steve

X2

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17 minutes ago, cactus said:

X2

 

9 hours ago, Steve from SoCal said:

The more I hear about facebook, twitter et al , the happier I am I never got started

 

Steve

X3  I tried Facebook but bad news results

Clay

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The op seems to be under the assumption that all hdt's have leaf springs. If you could get larger air bags to fit under the truck it would make it ride better, larger capacity equals less psi for the same amount of lift, but it would not solve the lack of side to side movement. I tow gooseneck trailers only so do not have that problem but I do use a air bag hitch that I moved from my one ton. There are half a dozen air ride type hitches available for gooseneck trailers that are usually being pulled by pickups, and the frame on a gooseneck is usually way stronger than on a 5vr. So I guess we are just wasting our money.  My neighbor, who owns about 15 semis, thinks I will brake my trailer anyway as the trailer has to take all its own shock when hitched to a truck that weighs as much as it does. That nice feeling of not feeling the trailer hit the bump comes at a cost, either damage to the trailer or a hitch that is made  to protect the trailer.

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GEEEZ  what a bunch of nice people.  I was just trying to get a few members input on what I'm going to do to old MY Truck.  I have owned and operated this 84 359 Pete for thirty years and know every inch of it.  I'm now retired and would like to modify it for my wife and I can travel.  I don't even have facebook account or want one.  People like Big5er's childish comment does nothing but spread hate and BS drama .  Looks like I found the wrong site I don't have time for games.

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RJHILL,

 

I guess you don't want to believe the reasons noted, you can do all the tricks you want to the back of your truck.    It still wont make towing an RV with a full size non articulating hitch "good" for the trailer.      You can ignore the answer I wrote and the other comments about the same issues, directly below mine.    I have no interest in any hitch maker or get a commission for offering advise.     The basic FACT is the RV trailer are not built like semi trailers nor do they have the strength in the hitch plate to withstand the torsional loads a semi trailer does.   

 

The answers are there, disregarding them is your choice.

 

Steve   

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6 hours ago, RJHILL said:

GEEEZ  what a bunch of nice people.  I was just trying to get a few members input on what I'm going to do to old MY Truck. 

 People like Big5er's childish comment does nothing but spread hate and BS drama .  Looks like I found the wrong site I don't have time for games.

There is not a single question mark in your original ramble. You didn't "ask" for any input. Your original post is one poorly phrase statement, not a question. Before you whine about the responses you received maybe you should look at the "question" you asked, thus my original response of "huh?" .

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RJHill, I agree with Big5er.  From your rambling mish-mash comment, I have no idea if you are stating a fact or asking for help.  You might want to rethink your post and try cleaning up the thought process.  You won't find more helpful people or better people than on this site.

Ken

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11 hours ago, RJHILL said:

GEEEZ  what a bunch of nice people.  I was just trying to get a few members input on what I'm going to do to old MY Truck.  I have owned and operated this 84 359 Pete for thirty years and know every inch of it.  I'm now retired and would like to modify it for my wife and I can travel. 

2

If you had put this info in your original post it would have given us an idea of what info you were looking for.  There are hundreds of people that join the forum, bash the big trucks and disappear.  

So now that we know that you have a classic Pete and want to soften the ride we may be able to offer helpful suggestions.

Suggestion number 1 is don't assume anybody knows what you're talking about.  Be as descriptive as you can in your questions.

Suggestion number 2 is do a Google search for "Semi Truck Ping Tanks" 

The most important part is that you don't need to change your driveline angle while softening the ride.

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  Sorry I didn't make the first post very clear and I apologize if I offended anyone.   All I was looking for input not grammar check or sarcasm (FB) .  Not saying I know everything about anything.  My father owns a trucking company with avg an of 15 -20 trucks and I have never had any class of license other then a class 1.  I am 65 years old retired and  have a very strong trucking back ground and have raced off road vehicles over 40 forty years which requires and extensive knowledge in suspension setup.   My 84 359 Pete was purchased new by the family and I have operated and maintained since new. 

Class 8 trucks have their spring rate frequency set for heavy loads (any type spring or air bag ) and they also have their dampening  (shocks) set at that spring rate frequency. This is all I was trying to say about putting a movable 5th wheel plate or spring box on a incorrectly sprung truck  .... not hating just pointing out a problem that will destroy a RV pin box.  I'm sure these movable hitches, pin boxes help and would work even better if the truck was correctly with spring rate and damping .   Please keep an open mind and watch these two short videos about spring frequency and damping of the movement.  

Spring rate frequency  (springs any type)

https://www.youtube.com/watch?v=4FZp_oDGQNY&t=1075s

Comp. & rebound damping. ( shocks movement control)

https://www.youtube.com/watch?v=-Wx2yH8fFbs

 

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Changing the spring rates and dampening is something that Brit Mansell was talking about this year at the ECR. Try hooking up with him and see what the two of you can come up with. By the way, he is a suspension system designer for off road vehicles and a great guy with a good engineering background.

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On 10/26/2018 at 8:05 PM, Alie&Jim's Carrilite said:

RJHills comments are probably coming out of the HDT group of Facebook.  There is a large group there that are pulling with commercial hitches and claiming to have no issues.  At this year's National rally in Hutchinson, there was a 2009 DRV with a failed pin box and frame that had been towed with an MDT and solid hitch.

I viewed that trailer, and while the rigid hitch/pin box connection was a big reason for the failure, there was another factor.  The steel framing around the pin box seemed to me to have been built with roll formed steel rather than using structural shapes.  As well, it looked like it was 12-14 GA, and no welds were put on the bottom of each member.  The welds broke but mostly what I saw was the steel ripping from the stress and the light duty materials used around the pin box.  Yes, a cushioned hitch would have helped, but that isnt the answer for poor design.

This failure was certainly due to a number of factors.

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I missed Brit's talk at the ECR this past year, and it would be wonderful is someone were to dial in what our spring rate should be and the dampening and rebound rates of the shocks should be.  Obviously since all of us (with the exception of some special order trucks) are/were set up for heavy loads (a lot more than any of us are using now) a known spring rate would be great!  Maybe Brit has figured it out and can share?  I'm pretty sure the truck companies aren't interested in working out these facts for trucks they may never sell.  When my Teton had 7K pin weight, the ride was fantastic!  And I was no where close to exercising my truck suspension.  But the newer DRV is really built for pickups and the light pin weights are not something any of us like.

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18 hours ago, RJHILL said:

GEEEZ  what a bunch of nice people.  I was just trying to get a few members input on what I'm going to do to old MY Truck.  I have owned and operated this 84 359 Pete for thirty years and know every inch of it.  I'm now retired and would like to modify it for my wife and I can travel.  I don't even have facebook account or want one.  People like Big5er's childish comment does nothing but spread hate and BS drama .  Looks like I found the wrong site I don't have time for games.

Actually, if that is what you would have done, it would have been more than fine. What you did do is say that changing hitches was the wrong thing to do and your way was "the correct way." That is not asking for input, that is telling everyone who you say you want "input" from, you are right and they are wrong. 

First, this topic has many, many, many, many, many posts in this forum. The search function is your friend and there is a lot of great info out there on the pros and cons of keeping the standard holland hitch or putting on an air ride hitch.

Second, this forum is great for info and to ask questions and the people are top notch. Just ask the question, do not start the post telling everyone they are wrong and you are right. Your choice, but collect all the info and then just make the choice that is best for you. 

Third, probably over 98% of folks on this HDT forum have rear air springs, not leafs.

Fourth, if you think your way is the way to go, then just do it and tell us how it works. I'm curious to see what the results are and how your trailer holds up.

Again, this is a great forum with lots of great people with excellent advice and experience towing 5th wheel RVs with HDTs. There was no hate and drama in Big5ver's "huh?" response. He is a wealth of knowledge and experience on the HDT and the legal side of things. I agree with him, your original post was more of a statement and not a question. 

and I would love to be able to set the air springs at a lighter weight load vs. just a height load. That would be awesome. if you can tell us how to do it, I would be most appreciative as would many others. 

Edited by lockmup68

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4 hours ago, RJHILL said:

  Sorry I didn't make the first post very clear and I apologize if I offended anyone.   All I was looking for input not grammar check or sarcasm (FB) .  Not saying I know everything about anything.  My father owns a trucking company with avg an of 15 -20 trucks and I have never had any class of license other then a class 1.  I am 65 years old retired and  have a very strong trucking back ground and have raced off road vehicles over 40 forty years which requires and extensive knowledge in suspension setup.   My 84 359 Pete was purchased new by the family and I have operated and maintained since new. 

Class 8 trucks have their spring rate frequency set for heavy loads (any type spring or air bag ) and they also have their dampening  (shocks) set at that spring rate frequency. This is all I was trying to say about putting a movable 5th wheel plate or spring box on a incorrectly sprung truck  .... not hating just pointing out a problem that will destroy a RV pin box.  I'm sure these movable hitches, pin boxes help and would work even better if the truck was correctly with spring rate and damping .   Please keep an open mind and watch these two short videos about spring frequency and damping of the movement.  

Spring rate frequency  (springs any type)

https://www.youtube.com/watch?v=4FZp_oDGQNY&t=1075s

Comp. & rebound damping. ( shocks movement control)

https://www.youtube.com/watch?v=-Wx2yH8fFbs

 

I understand what you are saying. Once you figure out what you are going to do and how you are going to do it, please share with the rest of us.  I for one am not willing to put smaller springs on my truck.  Yes I put a comfort ride hitch on for the camper but I am also putting a goose neck ball on. I want to be able to pull the 12 ton flat bed, 30 ft enclosed trailer, and 30 ft stock trailer (personal use not for the farm). 

One thing I did to improve the ride is I aired down my drive tires to 85psi. Right or wrong thats what I did. I didn't get a mile down the road and we could tell it rode real nice.

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