Demax990

My project what do u think?

44 posts in this topic

I am looking at buying a peterbilt with a c15 and 1.2million Kms on it to tow my 5th wheel. It does have a sleeper on it as well now here is the fun part. I have 3 small kids and we do lots of traveling in the summer time with the 5th wheel (37 feet) I would like to add a bench in the sleeper or seats instead of the bed that way the kids could ride in there with there car seats. I also do not want to have to drive it around when we get where we are going so I would like to stretch the frame to allow me to build a flat deck on the back. It would need to be long enuf for a yukon xl to ride on it (18 feet). What do you all think of this is it doable? How long would it need to be extended? Still learning lots but I am a dual ticked tradesman (automotive,millwright) so I do know my way around the tools. Any help would be appreciated thanks

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If you are pulling a 5th wheel hauling your 18' Yukon is going to need 24' bed. That's going to be really long wheelbase and or tail. I have one of the longer beds of the group and mine is roughly 20'.  It can be done no doubt but you have to ask yourself where you will be pulling as this length will impact maneuverability. 

If your pulling a travel trailer that is a different story. You will get a lot of answers and ultimately it comes down to what you want. 

What model Pete are you looking at?  Has the motor, transmission ect been overhauled?  

Whatever you decide just have fun with it. 

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6' is about all the overhang past the rear axle that you can put the hitch.  So you would need 14' from the rear most axle to the rear of the cab, plus the cab length to the front axle.  

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I was planning on keeping it a tandem and cutting the frame and pushing the axles back enuf so the the front of the yukon (backed onto the truck)  sat over the rear most axle.  meaning the centre of the rear axle wold be 18 feet from the back of the cab. The hitch would then sit about 3 feet back from the centre line of the rear  as well. So what I was thinking was a 20-21 foot deck. The last 3 feet of the deck would be on a slight angle downward and I would use ramps to get the yukon off.  Does anyone have pictures of a 20-22 foot deck on a tandem with a sleeper on it??? 

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Are you allowing enough room for fifthwheel?  If wide body it will need roughly 60" from center of pin to Yukon to allow turning/backing. We back at 24' deck. 

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Quote

 

Your front axle will most likely be a limiting factor if you have the tandems that far back.

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Three issues I see with what you are thinking.

1) add up up your overall length, you are probably going to be over length in most areas.

2) depending on what capacity the front axle is you may be exceeding the front axle capacity.

3) a long wheel base is going to be hard to turn which I'll make campsite access difficult

Dave

Edited by Star Dreamer

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Well  i will add what so many don't think of. The way i did mine i only have a 17' bed.but only loading Jeep 2 door but i gain 24" by putting on a sidewinder pin box on your RV. then your pivot point is moved under RV not at the kin pin. Anyone that has one for any reason would never go back to the conventional way. It cuts your turning radius of the entire rig. Also pulling the 5th wheel follows the tractor like pulling  pup trailers. You don't have to make that wide swing at every intersection. 

My RV is 44' behind a twin screw Volvo lengthened frame 5'. I will guarantee I can out turn most of the HDT Rv rigs on this forum that are much shorter than I am. Makes much easier to back (cuts faster sharper) plus the main reason is you can have your bed 24" shorter. Only way to go in my Opinion. See my Volvo build pics on comfortridehitch.com under gallery. hope this helps anyone. Rick

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D-MaX,,,,,,,

Welcome .....you have the forum where we tend to take not only the kitchen sink from home camping heck we take the garage with the sUV as well....

As you are hung up on taking a You-kon with you you might consider what Ronbo here on the forum did......he acquired a roll-off recovery truck bed so he just hope out and with the toggle of a few levers his Jeep is gently lowered to the ground with out ramps or drama.....just like the big bucks tow companies.....big player in the game is Jarrdan ($p).....

Turnkey roll off beds are pricey new but not too bad used ......

Weight and balance calculations are not bad once you obtain real baseline weights and locations....

Seldom is the toad in your current driveway the best fit for your camping combo......maybe time to consider something shorter......

Drive on.......(how long is .......2 long)

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Hey guys 

wow thanks for all the replies. So bumper to bumper on the yukon is 18'6". If I put the 5th wheel 2' from the yukon and use a sidewinder the pivot point on the 5th wheel would be 4' from the yukon as I believe the sidewinder adds 24".  So I could use a sidewinder with a 20' bed and still get the yukon not to hit the 5th wheel?  So if I go with a 20' bed would I need to cut the frame to extend or can I just add onto the back of the frame? I don't have the measurement from the rear of the sleeper to the rear most point so I do not know exactly how much longer I need to be? 

 

The 5th wheel also has giant cutouts in the front of it (from the factory) to allow you to turn with out hitting. I towed this trailer with my 2014 ram 3500 mega cab and I never used a slider and never came close to hitting and the hitch was super close to the  back of the cab. 

Edited by Demax990
Fixed it

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Subcompact cars typically 12 - 12 1/2 feet require 20 foot beds to accommodate clearance from cab to car, car to pin and fifth to car. It has been done numerous times before so that number is good. If Yukon is 18 feet you will need 26 FOOT LONG BED! 

That's an awfully long bed. Moving axles back is the only "real solution", overloading the front axle is a possibility.

 

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5 minutes ago, phoenix2013 said:

Subcompact cars typically 12 - 12 1/2 feet require 20 foot beds to accommodate clearance from cab to car, car to pin and fifth to car. It has been done numerous times before so that number is good. If Yukon is 18 feet you will need 26 FOOT LONG BED! 

That's an awfully long bed. Moving axles back is the only "real solution", overloading the front axle is a possibility.

 

Maybe I am missing something here but I just measured the centre of the jaws on a f250 to the cab and it is 3'6". Now my mega cab was much closer and I never hit or came close so using that logic and using a sidewinder I should be able to be 2'6" From the front bumper of the Yukon. Making overall length 21'. 

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I think you are confused, plan on 60" from the center of the fifth wheel to anything on the bed.    With a 18'6" burb you will need 23'6" with no forward clearance.    Plan on a 6" buffer to keep the cargo from interfering with cab movement.

That puts the pin 24' from the back of the cab but, remember to add what ever you need to account for the other half of the fifth wheel mount.    The bed would have to be longer.     Most average tandem tractors have about 8' from the center of the tandem to the back of the cab.   A truck with that axle placement would need about four feet of frame extension ahead of the tandems.    The pin weight that far back would also be a critical number in where the axles should go, perhaps 6' feet back.    A truck with 240" wheelbase would stretch to 300+" that is going to be like driving the Queen Mary.    With that kind of loading profile you most likely need ballast tanks to keep the front axle weight in range unloaded.

 

Steve 

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I still don't understand why you need so much room. I went to a 3/4 ton or 1 ton and the fifth wheel jaws to the back of the cab is 3 feet 6 inches. When I used the truck I could jack knife it no problem. I also had a mega cab and that was just under 3 feet from jaws to cab and still never hit or had issues. So why would I now need 60 inches when 36 inches was fine before?  So them 6 inch buffer 18'6" vechele and another 36 should be 22' long? 

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Is your trailer 6' wide?     A fifth wheel is in the center of the width of your trailer, a 102" wide trailer has a min swing of 52" with no allowance for corner swing really only an issue on deep pin placement.    So so need at least say 54" to keep from swapping paint in a 90 degree turn.   

Steve

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I figured out what's going on and why it works. Semi trailers are the full width at the front of them. 5th wheel campers are not. The front of them are rounded and the Corners are big concave cutouts. So to get the full width I would have to be 2 feet  or so from the front. The pin boxes for them also extend slightly past the front as well making the pin location in front of the trailer. 

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1 hour ago, Demax990 said:

Hey guys 

wow thanks for all the replies. So bumper to bumper on the yukon is 18'6". If I put the 5th wheel 2' from the yukon and use a sidewinder the pivot point on the 5th wheel would be 4' from the yukon as I believe the sidewinder adds 24".  So I could use a sidewinder with a 20' bed and still get the yukon not to hit the 5th wheel?  So if I go with a 20' bed would I need to cut the frame to extend or can I just add onto the back of the frame? I don't have the measurement from the rear of the sleeper to the rear most point so I do not know exactly how much longer I need to be? 

 

The 5th wheel also has giant cutouts in the front of it (from the factory) to allow you to turn with out hitting. I towed this trailer with my 2014 ram 3500 mega cab and I never used a slider and never came close to hitting and the hitch was super close to the  back of the cab. 

Maybe a picture of your 5th wheel front would help.  You say it has giant cutouts at the front for clearance, but I'm not sure what you mean.  If it's what i think you're talking about, the kind that hangs over the cab, I don't think that would work on an HDT to give you clearance over your Yukon. 

 

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31 minutes ago, Demax990 said:

I figured out what's going on and why it works. Semi trailers are the full width at the front of them. 5th wheel campers are not. The front of them are rounded and the Corners are big concave cutouts. So to get the full width I would have to be 2 feet  or so from the front. The pin boxes for them also extend slightly past the front as well making the pin location in front of the trailer. 

When camper is 90 degrees how far pin in front has no bearing. You need clearance from center of pin to edge of camper. Then add some for tilt. Wide body 60" good. 

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I can't seem to upload a picture???? However it is just a 2012 fifth wheel most new or newer ones if you look at the front of one you will see what I mean. They don't have 90 deg corners on the front. They are built for better turning clearance 

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The corner is NOT the issue, when you turn the trailer at a sharp angle the side of the trailer is at or near a right angle to the truck.    From the center of the trailer to the side is 51" with a bit of room for tilt etc plan on 60"

You may never make sharp turns with your pick up, I can say with no doubt a 300+ wheelbase truck you will.    

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3 minutes ago, GlennWest said:

When camper is 90 degrees how far pin in front has no bearing. You need clearance from center of pin to edge of camper. Then add some for tilt. Wide body 60" good. 

If you need 60" of clearance to tow a 5th wheel how do 1/2,3/4, and 1 tons haul trailers around with out smashing their cabs? The hitches are usually over the axles putting the hitch in the middle of the box. So if it a 6 foot box then they have 36" from the pin to the cab.

 

also what is the usual lenght of a tractor from the back of the sleeper to the end of the frame (rear) 

 

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Can you put a slider hitch so when I am going down the road I can have it as short as possible. Then slide it back when I need to do tight maneuvers.  Just really want a hdt but it just to big for sightseeing so that's where I thought of taking the wife's yukon as well. But I don't want it to be way to long 

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2 minutes ago, Demax990 said:

If you need 60" of clearance to tow a 5th wheel how do 1/2,3/4, and 1 tons haul trailers around with out smashing their cabs? The hitches are usually over the axles putting the hitch in the middle of the box. So if it a 6 foot box then they have 36" from the pin to the cab.

 

also what is the usual lenght of a tractor from the back of the sleeper to the end of the frame (rear) 

 

Short bed trucks generally use sliding hitches, many have damaged trucks and trailers for this reason.   

 

The example I gave earlier about a truck with a rough general axle placement of 8' to tandem centerline would have about 4-5' of frame beyond that so 12-13'     The last 12" or so" will be tapered.      A 24' bed on a truck should have about 60-65% of the bed forward of the tandem centerline.     That would extend most trucks by 6-7' in wheelbase.

 

The average truck is 120' BBC or from the nose to the sleeper, a 60" that is 15' plus a 24' bed min, more likely 26' puts the truck at 40-41' in length.    That is a bus, add a 35' trailer and you are way over length and there is no way visually it will go unnoticed.     

 

Steve

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