The Road Ranger. 1997 SEMI

[Rick W]

Good point, Thanks for the heads up.

Understood and considered. The load will be primarily downward, minimal other loading since it’s a ball in a cup, and the trailer axles will be in the rear, not half way. Enhances the downforce.

If you think about it, the forward backward loading is maximized during a hard brake, forward (assuming the electric brakes are set correctly). That will be against the front of the cup.

Pulling will be against the tightener, it’s bolt & cross pin. Have you ever seen them fail? My set up may cause more wear on them, but you can see it every time you look down.

I haven’t gotten this far, but there will also be chains from the frame to the tag axle, and cross chains on the trailer. This tag axle set up is technically a trailer, chains required, and all together technically a train. I’m not to worried about getting a ticket either way.

And finally, I’m probably only going to pull the empty trailer for fun and shows, no real work, and if so, rarely.

Having said all that, this all came to me in a dream, and my welding skills have deteriorated (I compensated with huge welds), so there are 6-7 spots I’m going to monitor very closely for wear or fatigue.

Again,

Thanks! All comments and concerns welcome!

 

[JoshT]

I've gotta agree with @2011Supercab on the hitch.

Understood and considered. The load will be primarily downward, minimal other loading since it’s a ball in a cup, and the trailer axles will be in the rear, not half way. Enhances the downforce.

If you think about it, the forward backward loading is maximized during a hard brake, forward (assuming the electric brakes are set correctly). That will be against the front of the cup.

Pulling will be against the tightener, it’s bolt & cross pin. Have you ever seen them fail? My set up may cause more wear on them, but you can see it every time you look down.

I don't know that I agree with your assessment here.

Forgive me if I'm mixing up some terminology here, it's been a long time since I took physics or any class dealing with laods and stresses on materials. The loading is maximized during breaking, but that is an impulse load. The impulse load may be heavier than the constant load, but it's also a lot shorter. Many materials can handle a much heavier load for a very brief perior than they can a light load for extended periods. Jumpoing from weights to electricity for an example. Think about a fuse or circuit breaker they can handle a brief spike higher than rated, but put that load on it for any longer and it's going to blow.

Yes, you may be removing the impulse load from the "tightner" but it is designed to handle that impulse load. Instead you are putting a constant load in it which it is not designed for. Your potential failure moved from being impulse laod to metal fatigue. The constant stresses placed on that piece over time may actually be worse for it than the impulse load that it was designed to take.

No, I haven't seen that piece fail, but I've also never seen it used in the application you are attempting to use it for.

I haven’t gotten this far, but there will also be chains from the frame to the tag axle, and cross chains on the trailer. This tag axle set up is technically a trailer, chains required, and all together technically a train. I’m not to worried about getting a ticket either way.

Again not sure that I agree with you here.

First, if it were technically a trailer, you would need to register and tag it independently from the truck. I have a feeling that will be neithier done or necessary. A 5th wheel dolly would be a trailer, but a 5th wheel dolly is not a tag axle or what you ahve designed here.

Second, a your design is similar to a ladder bar style syspension used on many vehicles, though yours is a little more intricate and maybe sturdier. It may be a "spare" axle, but it's just as much a part of the vehicle as an axle in anything else running this style of suspension.

I'm not discouraging running safety chains, but I don't see them as required or even needed. Safety chains exist for event of coupler breaking or coming loose (what we discussed above). Your tag axle setup isn't connected with a coupler, it's bolted into the vehicle as much as the drive axle or any other suspension component would be.

 

[lil_Blue_Ford]

So, I’m gonna jump on the bandwagon here with @2011Supercab and @JoshT …

That hitch was never designed for the use you’re proposing. I’m not a fan of ball hitches period. I haven’t had that tensioner thing completely fail yet, but I’ve had it fail to grab correctly twice over the years resulting in damaged bumpers on the tow vehicle. I knew right away something was wrong, but it’s already too late at that point. I much prefer true 5th wheel or pintle hitches. Much more secure. Easily visible how secure too.

 

[Roert42]

I imagine it would have been easier to use a regular goose neck setup. With a ball bolted to a plate bolted to the frame.

 

[Rick W]

Sorry for the late response, I don’t think I’m getting ticklers when someone posts here, and I did a little more research in light of the comments and concerns.

A few different thoughts.

As regards the pulling direction on the ball/hitch combo. I think this coupler is rated at 5,000#. In design, there is a engineering safety factor in loading anywhere from about 20% to 500%. The 20% is for things like plastic bags and Tupperware, use your imagination.

Anything that involves life safety would be over designed (and tested to failure) by a minimum of 100%. When you get into things like this hitch, it’s not only “individual” safety, it’s “community” safety: if it fails, you can hurt or kill a lot of folks, not just yourself. That’s where you get into greater (much greater) than 100%.

That combines with another concept, cost benefit analysis. You don’t jump to a 500% safety factor if the cost also goes up 500%. For this hitch, the additional metal and purity of the metal and stamping accuracy probably don’t vary by 5%, so it would push it up to a very high safety factor.

And finally, the use or misuse likelihood is also a factor in design (I’m not talking about my perverted use, yet). We all know trailer hitches can be abused by idiots who shouldn’t even be trusted to walk, so the design will be pushed higher, to try and idiot-proof it.

My point so far is that no matter what configuration is used, if it’s rated at 5,000#, no force in any direction should fail at less than maybe 8-10,000# loading, and the torques and forces created in a tumble.

Soooo, I’m not worried about it breaking.

The next concern would be premature failure from excessive wear by coupling in reverse. That may be a valid concern. The constant loading, as designed, is the front of the ball against the broad area of the cup. A very long wear out process. When braking, it’s a shock load against the tensioner (and cross pin and bolt through the locking lever).

The surface area of the ball against the tensioner is probably pretty similar to the ball to the cup. The pressure on the cross pin and lever-tensioning bolt are secondary, but that may be where premature failure could start.

Specifically, the cross pin could wear where it goes through the tensioner and/or the holes in the tensioner could egg out. Ditto for the tensioner bolt: bolt wear or bolt wearing the holes out. And finally, while the hard cross pin is pressed into the overall coupler almost like a rivet, it could shimmy loose.

In my use, these smaller pieces all face up, you can see and inspect them easily. Also, for my use, I will probably set the tension correctly every time. I doing so, it should be easy to spot wear and tear. While I’m crazy creative, I’m not actually crazy suicidal, so if I suspect any wear concerns, I swap to the other new coupler I got on Craigslist.

On chains and legality, I pooled several things together. Over simplified, this axle set up could be considered a trailer in the stretch of imagination, hence requiring chains. Since it is a ball hitch, the trailer definitely requires chains. And, as sure as I am about my “design,” chains are just an added safety factor. And finally, I’ll paint the chains red and yellow or silver or day glow orange, and they’ll just look kooky cool.

Remember I’m also not working like you guys, nor working the truck like you guys. It’s a toy, and most use will be empty or with a stuffed animal or soup can on top. If I do load it, it will be rare and never close to max. If I have to pull another Rodeo or such, I’ll use a car trailer on the lower receiver hitch, and maybe my F250.

I could go on about static failure vs fatigue failure, but that’s really overkill for what I’m doing.

Yes/no? Comments?

 

[Roert42]

Still feels like your over thinking it.

Reinventing the wheel as they say.

 

[Rick W]

Not overthinking, just explaining. Always keep in mind, for me, this is all just playing around. But I have gotten some great advice from a few of you folks.

And one last thought on a conventional fifth wheel set up. If I was doing this for work and my business, it would all be top-of-the-line first class. But the whole nature of this project and the other project is putting them together with what I find on the side of the road…

And I do appreciate all the comments, I am pretty safety conscious even though it’s a crazy project

 

[lil_Blue_Ford]

I still disagree with using a trailer coupler as you are no matter what the load or how minimal. IMHO, a 5th wheel hitch is what you need. But given that you don’t intend to significantly load it and you’re trying to keep costs down (entirely understandable), a simple gooseneck hitch would suffice.

The dynamics of pulling even an empty trailer down the road, actually probably especially an empty trailer as they tend to bounce around a lot more than a loaded trailer (ever tow an empty equipment trailer with ramps that pin to bars in a vertical position? That thing will rattle like all get out…). That puts a significant dynamic loading to the hitch. Going down a bumpy road or hitting a significant bump at highway speeds suddenly can very quickly go from fine to catastrophic failure with dynamic forces. Add to that loading your “hitch” in a manner which it was never designed for and I’m suspecting the hitch probably is a cheap chinesium and it’s a whole lot of nope in my opinion.

There are things I’ll go cheap on, and pulling a trailer isn’t one of them, especially after a chipper came off a tree service truck a few years back and killed a family near here. Smashed into their minivan and that was that. Right after a local police department lost its funding and closed. They had their police department back in days after the incident and they were stopping anyone with a trailer for spot inspections for a couple years after that. Nope, I don’t need attention like that. I got stopped a couple times back then and the cop looked at my massive pintle hitch setup with safety chains and just waaay over and above what’s needed for the size of the trailer and just wished me a good day.

That all said, @sgtsandman showed me his lock-n-roll setup and I’m thinking I might want to switch to that, it’s an improvement over the pintle that allows greater articulation in all directions without the slop that a pintle has. Naturally it’s also more expensive, but my hatred for ball hitches persists.

 

[Rick W]

I still disagree with using a trailer coupler as you are no matter what the load or how minimal. IMHO, a 5th wheel hitch is what you need. But given that you don’t intend to significantly load it and you’re trying to keep costs down (entirely understandable), a simple gooseneck hitch would suffice.

The dynamics of pulling even an empty trailer down the road, actually probably especially an empty trailer as they tend to bounce around a lot more than a loaded trailer (ever tow an empty equipment trailer with ramps that pin to bars in a vertical position? That thing will rattle like all get out…). That puts a significant dynamic loading to the hitch. Going down a bumpy road or hitting a significant bump at highway speeds suddenly can very quickly go from fine to catastrophic failure with dynamic forces. Add to that loading your “hitch” in a manner which it was never designed for and I’m suspecting the hitch probably is a cheap chinesium and it’s a whole lot of nope in my opinion.

There are things I’ll go cheap on, and pulling a trailer isn’t one of them, especially after a chipper came off a tree service truck a few years back and killed a family near here. Smashed into their minivan and that was that. Right after a local police department lost its funding and closed. They had their police department back in days after the incident and they were stopping anyone with a trailer for spot inspections for a couple years after that. Nope, I don’t need attention like that. I got stopped a couple times back then and the cop looked at my massive pintle hitch setup with safety chains and just waaay over and above what’s needed for the size of the trailer and just wished me a good day.

That all said, @sgtsandman showed me his lock-n-roll setup and I’m thinking I might want to switch to that, it’s an improvement over the pintle that allows greater articulation in all directions without the slop that a pintle has. Naturally it’s also more expensive, but my hatred for ball hitches persists.

I hear you loud and clear, but as I just posted in the “what did you do with Ranger today“ posting, I am building this for looks and fun, not designing it or building it for the best functionality for a particular purpose. Having said that, I am very confident in the safety of what I’m doing, for what I’m trying to accomplish, which is building a toy. Don’t for a second mistake that I really do appreciate all the input. I know it’s sincere from good people and I do take it to heart.

American tractor trailers rely on the tractor to maintain a lot of the lateral stability of the trailer. A typical fifth wheel allows the base plate to pivot, and of course the trailer can swivel, but what the trailer can’t do is roll side to side on the pin. All of that is very important when the tractor is “carrying“ half the load.

My “design” is typical of what they do in Asia. The closest thing here in the states are the “B trains” they use out west.

The third axle on my cab actually pivots up and down, it is not rigid on the frame. The Coupler sits 60-70% of the weight on that floating axle and maybe 30-40% of the weight on the Ranger drive axle. That floating axle will carry about 45% of the weight of the trailer, with just a little bit being “carried“ by the cab. Putting the axles on the trailer at the rear will carry the other half of the trailer weight. The important point is that starting with the third axel, the entire trailer assembly is being dragged/pulled behind the truck, not carried on top of and by the truck.

With the trailer axles at the rear, there is little or no chance of the front of the trailer pivoting up and trying to pull up out of the coupler. The Coupler is rated at 5000 pounds, and every other aspect of this is far over built to such a weight. As stated earlier, that 5000 pound rating is loading in any direction up down sideways, pivot, etc. Since the trailer is front weighted and rear weighted by putting the axles at the extremes, the main force on the coupling is the ball pushing down into the coupler. The pinch of the coupler should be more than adequate to prevent the ball from pulling out, and the only serious forces are radially from the center point. Again, the couple is rated for that in all directions. Since the ball will allow the trailer to pivot (rock) side to side, as opposed to a fifth wheel pin, there is nothing that is trying to pry the ball out of the coupler. The stability is in the flexibility. The outward placement of the rear trailer axles, and some sensible driving, should be more than necessary to keep the trailer from tilting excessively. Also, I don’t plan on ever loading anything on there that would be top-heavy. If I’m going to tow a car or such, I would use a traditional lowboy trailer (I’ve already done that) with the ball coupler in the receiver at the back.

Hey, I’ll probably never put anything on it that will scratch up the diamond plate…

Keep the comments coming

 

[lil_Blue_Ford]

I hear you loud and clear, but as I just posted in the “what did you do with Ranger today“ posting, I am building this for looks and fun, not designing it or building it for the best functionality for a particular purpose. Having said that, I am very confident in the safety of what I’m doing, for what I’m trying to accomplish, which is building a toy. Don’t for a second mistake that I really do appreciate all the input. I know it’s sincere from good people and I do take it to heart.

American tractor trailers rely on the tractor to maintain a lot of the lateral stability of the trailer. A typical fifth wheel allows the base plate to pivot, and of course the trailer can swivel, but what the trailer can’t do is roll side to side on the pin. All of that is very important when the tractor is “carrying“ half the load.

My “design” is typical of what they do in Asia. The closest thing here in the states are the “B trains” they use out west.

The third axle on my cab actually pivots up and down, it is not rigid on the frame. The Coupler sits 60-70% of the weight on that floating axle and maybe 30-40% of the weight on the Ranger drive axle. That floating axle will carry about 45% of the weight of the trailer, with just a little bit being “carried“ by the cab. Putting the axles on the trailer at the rear will carry the other half of the trailer weight. The important point is that starting with the third axel, the entire trailer assembly is being dragged/pulled behind the truck, not carried on top of and by the truck.

With the trailer axles at the rear, there is little or no chance of the front of the trailer pivoting up and trying to pull up out of the coupler. The Coupler is rated at 5000 pounds, and every other aspect of this is far over built to such a weight. As stated earlier, that 5000 pound rating is loading in any direction up down sideways, pivot, etc. Since the trailer is front weighted and rear weighted by putting the axles at the extremes, the main force on the coupling is the ball pushing down into the coupler. The pinch of the coupler should be more than adequate to prevent the ball from pulling out, and the only serious forces are radially from the center point. Again, the couple is rated for that in all directions. Since the ball will allow the trailer to pivot (rock) side to side, as opposed to a fifth wheel pin, there is nothing that is trying to pry the ball out of the coupler. The stability is in the flexibility. The outward placement of the rear trailer axles, and some sensible driving, should be more than necessary to keep the trailer from tilting excessively. Also, I don’t plan on ever loading anything on there that would be top-heavy. If I’m going to tow a car or such, I would use a traditional lowboy trailer (I’ve already done that) with the ball coupler in the receiver at the back.

Hey, I’ll probably never put anything on it that will scratch up the diamond plate…

Keep the comments coming

I understand where you’re going with it, but you’re still loading the coupler in a way it was never designed. Will it work? Maybe. Will it fail? I don’t know. If it was me trying to do it cheap, I’d do a gooseneck. It’s designed for what you’re doing. Or if I could get my hands on a 5th wheel hitch I’d do that since that’s the kinda look you’re really going for. But I’ve also seen/heard/had a lot of trailer failures and some aren’t bad and some are downright tragic. I deal with enough problems, I don’t need to tempt more. When an empty trailer hits a pothole at 70 mph and jerks the truck for an instant, I want to be confident that it won’t be the last time I feel that. Just how I look at it. Using something in an incorrect manner from which it was designed doesn’t always inspire confidence because I’ve seen things used incorrectly fail spectacularly. Smacking two hammers head to head is one of those. Lots of people do it, and unfortunately I have in the past, but when they shatter from the hit, and it does happen, it’s not pretty. If you have to drive one hammer with another, use a dead blow mallet. It’s safer. So a lot of my input is colored by what I’ve experienced or seen and yeah, I still do my share of arguably dumb stuff, but some things I’m a bit cautious on and this is one of them. I do, however, understand what you’re talking about and it makes a certain bit of sense, I personally just don’t trust it.

 

[bobbywalter]

Sorry for the late response, I don’t think I’m getting ticklers when someone posts here, and I did a little more research in light of the comments and concerns.

A few different thoughts.

As regards the pulling direction on the ball/hitch combo. I think this coupler is rated at 5,000#. In design, there is a engineering safety factor in loading anywhere from about 20% to 500%. The 20% is for things like plastic bags and Tupperware, use your imagination.

Anything that involves life safety would be over designed (and tested to failure) by a minimum of 100%. When you get into things like this hitch, it’s not only “individual” safety, it’s “community” safety: if it fails, you can hurt or kill a lot of folks, not just yourself. That’s where you get into greater (much greater) than 100%.

That combines with another concept, cost benefit analysis. You don’t jump to a 500% safety factor if the cost also goes up 500%. For this hitch, the additional metal and purity of the metal and stamping accuracy probably don’t vary by 5%, so it would push it up to a very high safety factor.

100 percent safety factor is not a given.



this truck is kewlz with a super.

 

[2011Supercab]

My point so far is that no matter what configuration is used, if it’s rated at 5,000#, no force in any direction should fail at less than maybe 8-10,000# loading, and the torques and forces created in a tumble.

This part is not designed to have that kind of constant load, it's only purpose is to hold the hitch down onto the ball.

When braking, it’s a shock load against the tensioner (and cross pin and bolt through the locking lever).

Properly adjusted trailer brakes will slow the truck down putting the load on the front of the coupler, not the tensioner.

 

[don4331]

Attempting to correct misconceptions from actual design issues.

A gooseneck hitch is the same ball and socket as a "bumper" hitch; both have limited ability to resist "lifting" forces. As a result, both have to have chains as a secondary method of attachment. On the other hand, your trailer should have >10% of its weight on the "ball". Therefore, for on-road conditions, there should be limited cases where there is no weight on the ball - so long as there is weight on the ball, the hitch and/or the ball have to fail before the hitch disengages.

On the other hand, a 5th wheel hitch, surround the joining surface of the pin with >200* of securing surface. The result is the pin can resist >12k lbs (SAE spec J133) of vertical for 100k cycles) As a result, safety chains are not required when 5th wheel is used.

@Rick W is proposing inverting the hitch, the ball and the loads, as a result, the weight of the trailer will be on the socket of the hitch just like a normal trailer, and the "tensioner" will have the exact same function/loads as a normal trailer. Bass ackards but it works.

My concerns are regarding the removing of the frame rear crossmember - it keeps the rear spring mounts the correct distance apart drive "spirited" cornering. One doesn't want the rear frame to fold should Rick accidently slide into a curb.

I also don't see in the pictures how Rick has attached the crossmember to which he is attaching his rear axle brackets/suspension. Ford uses 8 - 1/2" rivets spread over 6" x 4" pattern at the front to minimize load concentrations.

I also don't like battery and filler in close proximity....I'd sooner the battery was in a vented compartment on other side of the truck.

 

[2011Supercab]

@Rick W is proposing inverting the hitch, the ball and the loads, as a result, the weight of the trailer will be on the socket of the hitch just like a normal trailer, and the "tensioner" will have the exact same function/loads as a normal trailer. Bass ackards but it works.

He's not proposing it, the upside down part doesn't bother me.

It's that he is using the "tensioner" as the part that he will be pulling against.

If he turned the hitch around and was pulling against the cup, it would be a different story.

 

[snoranger]

I kinda agree with the others… it seems like you’ll always be pulling against the lock. It’s not designed to be loaded like that constantly. I’d be cautious.
We have 5th wheel adapters on a few of our wreckers.

They’re NOT cheap, but they’re not really complicated. You should be able to make something similar shape and strength pretty easily.