Possible to add a third axle on this trailer I bought?

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There is only Ingsoc.
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It looks like a strong trailer. Pintle hitch trailers are stronger built - in my experience. It is a '79 with 16.5" tires. Unsure if that could be a problem.

Hope this link lets you take a look and offer your opinion. https://www.truckplanet.com/jsp/s/item/7429278

Not really looking to trade unless it is for a three axle trailer. Long story there.
 
Is that the actual trailer you bought. Pintle hitch/lunette rings are stronger than a ball style hitch, but I can put a lunette ring on a 7gvw trailer if I wanted. That being said, it does look like a strong trailer. I see no reason why you couldn't add another axle. What is it's weight limit now, and what will you be putting on it(weight) and what are you pulling it with. I don't buy any trailers with odd sized wheels, or odd mounting wheels.

@pioneerguy600 could we get this moved to the appropriate forum section :).
 
Is that the actual trailer you bought. Pintle hitch/lunette rings are stronger than a ball style hitch, but I can put a lunette ring on a 7gvw trailer if I wanted. That being said, it does look like a strong trailer. I see no reason why you couldn't add another axle. What is it's weight limit now, and what will you be putting on it(weight) and what are you pulling it with. I don't buy any trailers with odd sized wheels, or odd mounting wheels.

@pioneerguy600 could we get this moved to the appropriate forum section :).
I never found a weight rating for it. It is a '79 by the way. Judging by the 8 lug nuts and general weight ratings of 16.5" tires I suspect they are 7K axles.

But finding axles for 16.5" tires could be prblematic unless they are the same size as modern 235/85r16 trailer tires. I'll know more after I pick it up.

Hope I can put "bearing buddy" thingies on them. I hate greasing inner and outer bearings. Hate it.
 
Is that the actual trailer you bought. Pintle hitch/lunette rings are stronger than a ball style hitch, but I can put a lunette ring on a 7gvw trailer if I wanted. That being said, it does look like a strong trailer. I see no reason why you couldn't add another axle. What is it's weight limit now, and what will you be putting on it(weight) and what are you pulling it with. I don't buy any trailers with odd sized wheels, or odd mounting wheels.

@pioneerguy600 could we get this moved to the appropriate forum section :).
Forgot to answer everything. I bought it for my skid steer but I'd like to be able to move my 21,000 lb mulcher with it. I know that exceeds things due to trailer weight but dually trucks can handle a lot of weight riding on the rear. The genersl purpose of a dually - more or less.

I did buy a broken 2010 Freightliner Cascadia with DD13. Someday that should be available for heavy hauling. Some day.
 
Personally I would not put a third axle under it. It is hard to tell in the pic but it looks to have singles. The 16.5 tires are literally non existent so those have to go. If you are tied to that particular trailer I would put two new heavy 12/14k tandem axles under it. Even then hauling 21 k is going to be at the full upper limits. You will need to scale the trailer before you do anything. You have to know what it weighs first
 
Personally I would not put a third axle under it. It is hard to tell in the pic but it looks to have singles. The 16.5 tires are literally non existent so those have to go. If you are tied to that particular trailer I would put two new heavy 12/14k tandem axles under it. Even then hauling 21 k is going to be at the full upper limits. You will need to scale the trailer before you do anything. You have to know what it weighs first
Yep, probably weighs 5-6k, subtract that from 21 with three axles, and it's gonna be a bit over lol.
I'm almost done with this one. It's only 12k, but it should weigh 3k or just over I figure. Just need ramps and a couple spots on the aluminum welded, and three more 4" strap winches put on(there's four in front of the axles right now. It's light compared to my all steel 20' load trail 10k, and I get better fuel economy pulling it with my big tractor on it than my 20' with the little tractor on it and about the same as my 14' with a 5k single axle also a load trail that I can haul either tractor on.
 

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In no way am I being critical of try to make the trailer work. In today's world s lot of creativity and adaptation has been lost. We need to try to adapt things more and buy less. With that being said I have to be a bit negative but do not take offense. If that trailer does indeed have singles and it was factory made I would question how heavy built it actually is. It may look heavy but until you really look it over you will not know. I personally cannot see two single tire axles under a trailer that looks like that. If they are 7k and the trailer weighs 5000 that does not leave you much. Also you said you want to pull it with a dually. That is fine but before I went sinking money in that trailer I would load it as heavy as I cod to what you think the current limit is. Put that behind your truck and see what your tongue weight is. In looking at the pics the axles are set back a good distance which is good but will transfer a lot of the load to the hitch. Yes that will increase the weight capacity of the trailer but might put too much on the truck. There is a reason those trailers are mostly pulled by dump trucks. Yes pickups pull pintle trailers all the time but I am betting if you take a look you will see those trailers have the axles set further forward to allow a more balanced load and not so much on the truck
 
In no way am I being critical of try to make the trailer work. In today's world s lot of creativity and adaptation has been lost. We need to try to adapt things more and buy less. With that being said I have to be a bit negative but do not take offense. If that trailer does indeed have singles and it was factory made I would question how heavy built it actually is. It may look heavy but until you really look it over you will not know. I personally cannot see two single tire axles under a trailer that looks like that. If they are 7k and the trailer weighs 5000 that does not leave you much. Also you said you want to pull it with a dually. That is fine but before I went sinking money in that trailer I would load it as heavy as I cod to what you think the current limit is. Put that behind your truck and see what your tongue weight is. In looking at the pics the axles are set back a good distance which is good but will transfer a lot of the load to the hitch. Yes that will increase the weight capacity of the trailer but might put too much on the truck. There is a reason those trailers are mostly pulled by dump trucks. Yes pickups pull pintle trailers all the time but I am betting if you take a look you will see those trailers have the axles set further forward to allow a more balanced load and not so much on the truck
I agree with everything you said here except this.

Yes that will increase the weight capacity of the trailer
I get what you mean though.

Personally I'd want to sell this one and find one better suited to haul heavier. I see some nice trailers in the 5-7k range that are quality built and can handle a 10-14k load. Many of the hotshot haulers(dually trucks) are getting out of the business and they have some nice equipment they are letting go for 25-50% of what it cost new.
 
I agree and personally if I wanted to haul 21,000 I would even touch that trailer. I just didn't want to be quite as blunt as I sometimes am. I also would never attempt it on the bumper of a pickup.

As for my comment about increasing the weight capacity. I based that on when you increase bumper weight you are taking it off the trailer axles. My theory might not be true but I think it is. If you have a pickup and a tandem axle trailer you will have four total axles. If your gross weight of the package is 30,000 and you weigh each axle separately you will find as tongue weight increases weight will come off the trailer axles thus increasing the capacity
 
In my experience 3 axles pull markedly harder than 2; hardly ever hooked up to a 53' 3-axle and not felt that the brakes were dragging comparable to the same length 2-axle similarly loaded. Something about that third axle...

So if you can get the same weight-carrying capacity needed with 2 axles instead of 3, you'll spend less on fuel when towing.

I agree with the apparent strength of the trailer, it does seem it is intended to be used behind a dump truck and too heavy for a pickup of any kind. I just recently checked for my Dodge, and its max combined is 21,000 lbs; highest for a dually is 29,000. I could also only license up to 18,000 without having to have an annual commercial vehicle inspection on the truck. But I'm sure you knew those rules for your jurisdiction.

Personally I would not consider towing that weight of trailer behind a pickup of any kind as a bumper-pull. Just personal opinion I know, but it does come from experience.

Interestingly in just the last month up here where I am in the Cariboo district of BC, within 40 minutes drive, there have been 3 whiplash accidents on Highway 97; all seem to be from the trailer being loaded with too much weight behind the axles. Two of them I did see; the first was an aluminum ~ 20' tandem-axle travel-trailer pulled by a pickup all ending up on its side in the opposing lanes, second one I only saw the skid marks but within 100' of the first one. The third was 40 minutes further south and happened right in front (less than 1/8 mile) of me, a pickup towing a tandem-axle car trailer with lumber loaded, obviously (visually from driving slowly past with dust still settling) with weight too far aft. He ended up in the ditch on the opposite side from where he was travelling. To see 3, within a month, in so small an area says we have a driver's licensing problem.

The other interesting observation was that all 3 happened after the drivers had successfully got to the bottom of long downgrades, both around 8% and a couple of miles long. That the trailers were loaded to be unstable is obvious, but how they got to the bottom of the hill and THEN lost it is not. I see two possibilities; one that they released brakes when thinking 'whew, I made it' and increased speed beyond all possibility of maintaining stability, or when they released brakes after negotiating the hill one side on the trailer released before the other and set off the oscillation.
 
Last owner used it to carry a 22,000 lb. backhoe. It is extremely stout. The tires are rated at over 4,000 pounds and built in 2018. Amazon carries 16.5" tires.
I could add another axle but am now thinking it doesn't need one. The bearings are hyuuge.
Now if I used it for longer trips that might change things a bit. But I own nothing that weighs 22K and stay very local as well. Ingsoc in 3...2...1.
 
Last owner used it to carry a 22,000 lb. backhoe. It is extremely stout. The tires are rated at over 4,000 pounds and built in 2018. Amazon carries 16.5" tires.
I could add another axle but am now thinking it doesn't need one. The bearings are hyuuge.
Now if I used it for longer trips that might change things a bit. But I own nothing that weighs 22K and stay very local as well. Ingsoc in 3...2...1.
Ok....You posted on here looking for advice.
You received advice.
Your mind was already made up.
Seems odd but that is par for the course.
You say Amazon carries 16.5" tires that will carry 22,000lbs PLUS the weight of the trailer on FOUR TIRES.
Please shoot me that link.
I have an old 1978 Triggs livestock trailer that has 16.5's I want to see these amazing tires.

By the way what pickup truck was the former owner hauling 22,000lbs plus the weight of the trailer behind????????? That is one stout son of a gun of a pickup based on the toungue weight transfer of the axle placement
 
In my experience, tri-axle trailers are hard to get right, even from the factory. Shoot, nowadays, even dual axle trailers are leaving the factory and people are getting unevenly worn tires after a thousand miles. It's just hard to get the axles "square" with each other, even from the factories sometimes. Add a third axle into the mix, and one that's added by a "shade tree mechanic" (no insult intended), and it sounds even more difficult to me.

And unless it's been removed, or they did things differently in '79, all trailers come with a GVWR sticker on them, unless somebody's removed it. Adding a third axle will obviously up your towing ability, but you won't be "legal" by any stretch of the imagination. That's up to you though, I'm not telling you what to do or not to do.

Most tri-axle trailers have GVWRs of 21-25K, as they're almost always 7K axles, and the manufacturers take the GWR of the axles and then add another 15% to the capacity, figuring that 15% of that weight will be transferred to the towing vehicle (at least in a gooseneck situation, not sure about pintle hitch case).

@chipper1 I was going to tag you in this post, until I saw that you were already involved, as you're the "heir apparent" at making/modifying trailers. You beat me to the punch!
 
...............Most tri-axle trailers have GVWRs of 21-25K, as they're almost always 7K axles, and the manufacturers take the GWR of the axles and then add another 15% to the capacity, figuring that 15% of that weight will be transferred to the towing vehicle (at least in a gooseneck situation, not sure about pintle hitch case).
The problem is this is a bumper pull with the axles set way to the rear and you are leaving off the weight of the trailer.
 
Ok....You posted on here looking for advice.
You received advice.
Your mind was already made up.
Seems odd but that is par for the course.
You say Amazon carries 16.5" tires that will carry 22,000lbs PLUS the weight of the trailer on FOUR TIRES.
Please shoot me that link.
I have an old 1978 Triggs livestock trailer that has 16.5's I want to see these amazing tires.

By the way what pickup truck was the former owner hauling 22,000lbs plus the weight of the trailer behind????????? That is one stout son of a gun of a pickup based on the toungue weight transfer of the axle placement
I agree.
Looked at the 16.5 tires the other day after reading this, couldn't find any that would hold any weight like he's talking.
I have the heaviest rated hitch on my excursion I've ever seen on a truck, have air bags, and I'm also fairly proficient at loading a trailer, but I wouldn't want to run 22k on mine or a dually for that matter.
 
The problem is this is a bumper pull with the axles set way to the rear and you are leaving off the weight of the trailer.
No, I understand (at least I think I do, unless I'm missing something). I know the weight of the trailer obviously accounts for some of the weight of the GVWR of the trailer. Actually, now I think I AM missing out on what you're trying to tell me.

Actually, "LEGALLY", adding a third axle to the trailer will LOWER the payload capacity of the trailer, unless a person was somehow able to get the trailer re-inspected, and have it's GVWR upped. Because the trailer will now be carrying the added weight of the third axle, which will lower the amount of payload that can be legally added to the trailer.
 
I agree.
Looked at the 16.5 tires the other day after reading this, couldn't find any that would hold any weight like he's talking.
I have the heaviest rated hitch on my excursion I've ever seen on a truck, have air bags, and I'm also fairly proficient at loading a trailer, but I wouldn't want to run 22k on mine or a dually for that matter.
The 16.5 tires I see on there are light truck tires and I am betting when you get them they are not even 16.5. You are 100% spot on as they will not hold any weight. It was mentioned they are rated at 4K well great a 28K load on 4 tires rated a 4K what could ever go wrong...............
 
No, I understand (at least I think I do, unless I'm missing something). I know the weight of the trailer obviously accounts for some of the weight of the GVWR of the trailer. Actually, now I think I AM missing out on what you're trying to tell me.

Actually, "LEGALLY", adding a third axle to the trailer will LOWER the payload capacity of the trailer, unless a person was somehow able to get the trailer re-inspected, and have it's GVWR upped. Because the trailer will now be carrying the added weight of the third axle, which will lower the amount of payload that can be legally added to the trailer.
Bumper pull trailers and personal pickups that stay in the state of Illinois are not inspected nor subject to USDOT regs. I am sure others are different. Now since I live right on the border we do have a bit different laws.
 
The 16.5 tires I see on there are light truck tires and I am betting when you get them they are not even 16.5. You are 100% spot on as they will not hold any weight. It was mentioned they are rated at 4K well great a 28K load on 4 tires rated a 4K what could ever go wrong...............
I've hauled loads heavier than most, and also overloaded more than most, both that I should have been; and that I shouldn't have been, so I now that tire weight ratings are not going to always mean you can't haul an amount, but you may be pushing your luck too. DOT is quick to look at tire ratings when inspecting trucks, then at axle ratings, and I try not to mess around with that since I know better.
Don't worry, he'll just need to put 12k on the hitch, mine won't even do that, it's 2k hitch weight and 20k gross.

Here's a nice load for you, this was pretty common for a cross town load, but not one you'd want to pull across the scales. While it's totally legal to haul gross weight/permit wise, it's hard to scale it, so you'd want to loose a couple thousand pounds before going across michigan with it on a similar setup. A nice all aluminum trailer with super singles, you could put even more on it and run across the state.
 

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