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Trailer suspensions

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MarkEagleUSA

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I'm looking for a 10000 GVWR wood deck tandem axle car hauler or equipment trailer primarily to haul my new John Deere 1025R tractor. I don't think a 6k or 7k trailer gives me enough cushion with a 3000-3500 lb machine plus a couple of additional implements.

Anyway, I'm confused by the suspension options. Many of these trailers come with slipper springs which to me are low budget items. I'm more familiar with the double eye springs with an equalizer. There's also torsion axles. Which of these is best? Why?

What's the main advantage to torsion axles? Are they worth the premium cost?

Are slipper springs adequate with heavier loads?

Any help or insight appreciated.
 
Once you tow a trailer with torsion axles you will never go back. Leaf springs are cheaper but have much more bounce when empty. And they will need maintenance of the eye bushings, equalizer, and shackles. A Torsion axel has no moving parts the axle is the spring and shock all in one. The bad is you need to keep the trailer frame level to the road to keep both axles evenly loaded. I have owned both kinds of axles on my boat trailers. I will never own a leaf spring axle again. I have a pair on my sailboat trailer when the frame fails from rust I will order a new trailer with torsion axles.
 
I agree with ED. The slipper spring is actually way heavier duty than the double eye shackle type. The double eye is rated up to about 10-12k, the slipper starts at about 12k and goes all the way to 24k. Both types are high maintenance.

Torsion is my go to axle. Dexter has a 5 year warranty on spring axles, 10 years on torsion. Lippert is 6 and 11.
 
I have a 2000 Haulmark 20' enclosed car hauler with 3500 lb dexter torsion axles I store and haul my 04 MF 2814 4x4 compact tractor with front end loader and backhoe with no problems. The backhoe is heaviest attachment and my rear tires are 75% filled with water/antifreeze mixture. More is ALWAYS better, but my 7700lb rated car hauler works fine.

Let us know what you get.

Cheers, Ron
 
Once you tow a trailer with torsion axles you will never go back. Leaf springs are cheaper but have much more bounce when empty. And they will need maintenance of the eye bushings, equalizer, and shackles. A Torsion axel has no moving parts the axle is the spring and shock all in one. The bad is you need to keep the trailer frame level to the road to keep both axles evenly loaded. I have owned both kinds of axles on my boat trailers. I will never own a leaf spring axle again. I have a pair on my sailboat trailer when the frame fails from rust I will order a new trailer with torsion axles.

I disagree on an empty trailer, or even a partially empty trailer. Loaded and I agree, depending on the terrain. Empty torsions bounce a lot more for me, of all our trailers the only tandem axle one I've had bounce repeatedly is the torsion one. I'm not talking bounce like a single axle trailer, just minor bounce, but still not something I've experienced with double eye leaf springs.

We have a 16' stock trailer with 7K Dexter Torsion axles. Loaded up with 3 horses it tows great, but when empty (still ~4K lbs) the axles have zero, and I mean zero, movement to them..no give, no movement, basically no suspension. Speed bumps pull tires in the air (saw this today as I did 760 miles towing it).

Years ago I was talking with Dexter about re-clocking the axles (we'd like it to be 2-3" higher since we mainly use it on back roads) and also asked about the tires leaving the ground from bounce and bumps/backroads. They asked me what the axle load rating was, and what the load was on them. They said that they don't recommend torsion unless they are loaded at least 60% all the time. Empty the trailer has 3900lbs on the axles (scaled today), and loaded with 3 large horses (quarter/draft crosses) it has 7300lbs. (only 50% with a trailer that's 75% full of animal). Put a couple chords of wood in that thing and yes, yes, yes to torsion :)

Dad bought it in 05 and its been a great trailer, but to do it over I don't think we'd get torsion or 14K due to the loading and ground clearance.

To make a long story longer, torsions are great if you're loaded at least 60% most the time and don't need the ground clearance (thou there are 3 different clock positions they are sold in and ours is the lowest of the 3 and not adjustable). So it's not as simple as it sounds, at least in my experience.
 
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I disagree on an empty trailer, or even a partially empty trailer. Loaded and I agree, depending on the terrain. Empty torsions bounce a lot more for me, of all our trailers the only tandem axle one I've had bounce repeatedly is the torsion one. I'm not talking bounce like a single axle trailer, just minor bounce, but still not something I've experienced with double eye leaf springs.

We have a 16' stock trailer with 7K Dexter Torsion axles. Loaded up with 3 horses it tows great, but when empty (still ~4K lbs) the axles have zero, and I mean zero, movement to them..no give, no movement, basically no suspension. Speed bumps pull tires in the air (saw this today as I did 760 miles towing it).

Not a disagreement John, just adding some thoughts/experience to the discussion.

If the trailer is empty what does it matter if one tire is off the ground or even loaded? That is what is giving you a good ride, the independence of the axles. With a spring/equalizer suspension you will take a hit each time the axle (2) crosses a dip/ditch/bump, any irregularity in the road surface. With torsion axles they have a tendency to glide over bumps, one axle supports the other.

The bigger the truck v/s the trailer, the better the ride. When the trailer out weighs the truck the more important the suspension is. I feel every single rough spot with my Lamar dump (springs) @ 16-18k gvw towing with an 8k truck. The same truck towing my PJ dump, same loads with torsion and I barely feel the bump.

The OP is looking at a 10k gvw trailer, so since the truck will mostly always out weigh the trailer, suspension is probably fine either way. With personal use (seldom) maintenance is probably not an issue.

Picture of my PJ dump with one tire in the air:D

0917201409.jpg

Picture of my Lamar dump (springs) with frame/axle contact. Big loads and bad roads.

0914201403.jpg
 
Not a disagreement John, just adding some thoughts/experience to the discussion.

If the trailer is empty what does it matter if one tire is off the ground or even loaded? That is what is giving you a good ride, the independence of the axles. With a spring/equalizer suspension you will take a hit each time the axle (2) crosses a dip/ditch/bump, any irregularity in the road surface. With torsion axles they have a tendency to glide over bumps, one axle supports the other.

For me the ride is not better when the trailer is pulling/bouncing tires so easily. The torsions pull the tires so easily since they take a lot of weight to move the torsion, vs a springs that will move the other axle with the equalizer, which keeps tires planted. Unloaded, even thou it’s over 4K lbs, our stock trailer feels like it doesn’t even have a suspension.

No doubt that a well loaded torsion axle is a great thing, it’s the unloaded I don’t like.

I’m not saying don’t get a 10K torsion axle trailer, I’m saying if it will be towed empty a lot I’d think about something else. If it will mostly be loaded at 60% if it’s axle ratings, or more, go for it.

For the tractor the OP is talking about I’d be getting a 7K torsion or a 10K leaf spring trailer, but not a 10K torsion. The shipping weight of the tractor is under 1500lbs, so even with some accessories and filled tires a 7K should be plenty.
 
My car hauler has enough weight empty, it never has the bounce of an unloaded flatbed. I like the torsion suspension as it allows the trailer to sit lower and has more between the fram rails clearance. I have a 5.5' x 10' utility trailer with leaves that bounces like crazy empty, but I expect that. It's not uncontrollable, but you know it. My dump trailer has leaves and has terrible bounce empty, but G rated tires inflated max 110lbs and heavy leaves I expect empty bounce, even though it weighs 7KLBs empty. RV has IS torsion with shocks that performs great with 21KLBs.

I've been towing heavy generators with both types of suspensions... I prefer the torsion again for low profile and easier to change a tire with roll on tire changer.

Anyhoo, both work and have advantages and disadvantages. I get great service from both.

Cheers, Ron
 
The shipping weight of the tractor is under 1500lbs, so even with some accessories and filled tires a 7K should be plenty.
It adds up quick. The 7k (actually 6k rated) trailers seem to come in at 4000-4200 capacity. Not much margin left over.

Tractor 1500
Loader 500
Backhoe 600
Filled rear tires 180
Rear wheel weights 145
Rear ballast box 600
Grapple 300
Box blade 400
Tiller 700

I probably won't need to move all of this at once but it would be nice to know I can. Plus, if I upgrade the machine I want to make sure I can still haul it.
 
Sundowner blocked the axles for me when I asked for more ride height. They said clocking the torsions for ride height is a bad idea, and also stated torsions need sufficient load to work right. They need to be sized and clocked correctly for the application, so it's a case of more is not better.
 
I have a 5.5' x 10' utility trailer with leaves that bounces like crazy empty, but I expect that.

Cheers, Ron

At 10’ I’m guessing that’s single axle?

Anything single axle will bounce like crazy. We also have a 5’x8’ torsion single axle cargo trailer. Even on smooth roads it seems to spend more time in the air than on the pavement. Just the nature of the beast with any single axle trailer, and why I prefer to avoid single axle.


It adds up quick. The 7k (actually 6k rated) trailers seem to come in at 4000-4200 capacity. Not much margin left over.

Tractor 1500
Loader 500
Backhoe 600
Filled rear tires 180
Rear wheel weights 145
Rear ballast box 600
Grapple 300
Box blade 400
Tiller 700

I probably won't need to move all of this at once but it would be nice to know I can. Plus, if I upgrade the machine I want to make sure I can still haul it.

It can add up, and depends on if you’ll be hauling it for use or using it at home and hauling occasionally too.

What do you mean the 7K trailer is only 6K rated? That’s not something I’ve seen when trailer shopping.

Sundowner blocked the axles for me when I asked for more ride height. They said clocking the torsions for ride height is a bad idea, and also stated torsions need sufficient load to work right. They need to be sized and clocked correctly for the application, so it's a case of more is not better.

Exactly my point on torsion.
 
At 10’ I’m guessing that’s single axle?

Anything single axle will bounce like crazy. We also have a 5’x8’ torsion single axle cargo trailer. Even on smooth roads it seems to spend more time in the air than on the pavement. Just the nature of the beast with any single axle trailer, and why I prefer to avoid single axle.

John,

Agreed, it serves the purpose I purchased it for, but I'm not complaining about it and don't have a problem with it. I use it with my Jeep Wrangler and seldom tow empty. It is what it is. ;):D

Cheers, Ron
 
What do you mean the 7K trailer is only 6K rated? That’s not something I’ve seen when trailer shopping
According to what one dealer told me, axles come in 3500, 5200, and 6000 lb ratings. Two 3500's is 7k (duh ;) ) but the GVWR takes into account the rating of the wheels and tires as well (the weakest link theory). 7k becomes 6k, 10.4k becomes 9900, etc.

I looked at a nice used equipment trailer advertised as 10k but when I looked at the tag it stated axle capacity at 4k each. The salesman said no need to worry about what it says, it has 5.2k axles. That sent up a red flag for me and I passed on it. Now that I understand a little more, I'm wishing I had bought it.


Having never trailer shopped before this is all new to me.
 
According to what one dealer told me, axles come in 3500, 5200, and 6000 lb ratings. Two 3500's is 7k (duh ;) ) but the GVWR takes into account the rating of the wheels and tires as well (the weakest link theory). 7k becomes 6k, 10.4k becomes 9900, etc.

I looked at a nice used equipment trailer advertised as 10k but when I looked at the tag it stated axle capacity at 4k each. The salesman said no need to worry about what it says, it has 5.2k axles. That sent up a red flag for me and I passed on it. Now that I understand a little more, I'm wishing I had bought it.


Having never trailer shopped before this is all new to me.

Wheels and tires should match axle capacity.

Since there will be tongue weight you can have a GVWR higher than the combined axles.

The trailers I’ve looked at, since I’m still ATV trailer shopping, that have a pair of 3500’s do have a 7K GVWR.
 
Another thing: I don't want to skimp on a trailer to transport $25-30k worth of equipment.

Besides, isn't one of TDR's mantras "bigger is always better"? ;)
 
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