Why I think axleless suspension is pointless.

[gudmund]

"working on it's" trailer suspension pictured on the left w/his 'home-made' bump stop setup / mine on the right w/Sumo spring$$ set-up credit for the 'blending' of these two picture's goes to him - "not" me..............

[twisted lines]

"working on it's" trailer suspension pictured on the left w/his 'home-made' bump stop setup / mine on the right w/Sumo spring$$ set-up credit for the 'blending' of these two picture's goes to him - "not" me..............

You should give demo rides, I bet that's smooth

[gudmund]

and to think - I was just in your neck of the woods at the Redwoods get-together the end of last September = you could had gotten one than ..... oh well, maybe next time take care ..................

[Squigie]

I will say, to my consternation, I've seen air under our tires a few times (...)

It happens. I was very unfortunate last year. (Though fortunate that it was the last trip.)

I have some repair work to do on the tent trailer when the weather warms up. On the last trip home last year, a large (like 2'x3'x14") chunk of concrete, on a saw-cut but not actively under construction bridge transition, got flipped up by the van, and LAUNCHED the trailer. I saw the driver's side tire in the middle of my mirror - which means it was well over 3 feet off the ground.
I pulled over and gave it a quick check. Tires, wheels, axle, frame, tongue, and lights were okay. So I pushed on home.

As soon as I parked it and tried to set it up, I made some discoveries that were disheartening. The inevitable return to the ground was very, very hard on the bed supports, slides, lift mechanism, and the massive extrusions that serve as wall caps and a tie in point for everything structural. Those extrusions, in particular, were pretty much broken off the walls and resting on the counter tops (this is bad in like 394 different ways). I band-aided it together so it wouldn't leak or get worse over the winter.
But I have a lot to do in the Spring.

Torsion axle. (The one already sagging before this happened.)

But I don't think the type of suspension really matters when you hit a chunk of concrete the size of a Saint Bernard.

If the trailer was insured for replacement, I would have tried to have it totaled by insurance. But, it was not and is not.

[working on it]

... I saw the driver's side tire in the middle of my mirror - which means it was well over 3 feet off the ground.
I pulled over and gave it a quick check. Tires, wheels, axle, frame, tongue, and lights were okay. So I pushed on home.
...
Torsion axle. (The one already sagging before this happened.)

But I don't think the type of suspension really matters when you hit a chunk of concrete the size of a Saint Bernard.....

* I saw the same sight in my rear view mirror, and similarly, I pulled over in an empty parking lot to check my stuff out. I disconnected the trailer and drove around in just the truck; that's when I found the two busted belts in the 10-ply LT tires. I jacked the trailer off the ground, and looked it over, spinning the wheels; they were still round!

* Since it was late Sunday afternoon in East Texas, I couldn't locate a tire dealer that was open, so I limped (50-55 mph) most of the 150 miles home, though I sped up to 65 thru Dallas, to keep from getting run-over. The jarring ride home shook my tailgate handle trim off, and also opened the tailgate...twice before I strapped it shut. I'm really surprised that I made it home safely.

* After I replaced the damaged truck tires the next day (I bought four new LT tires), I went over the trailer thoroughly. A lot of loose items inside had gone flying, but the structure itself showed absolutely no damage. It sure checked out my frame & suspension welds.
And it's a good thing I built the cabin of 3/4" plywood with steel hardware and tons of PL adhesive, otherwise it might've come apart.

* That was six or seven years ago, and there's still no sign of damage. Yep, it is an over-built leaf spring suspension, with design and all welding done by me (my first welding project, alone).

[randb]

I will get back to you all. I am about to put 900kg HD Timbren on my new chassis. It has to be better than the current slipper springs currently in use.

Sent from my SM-N960F using Tapatalk

[schnottus]

I put 1 tonne Timbrens on mine. She came in a little lighter than expected (1380lbs) but the suspension is still super smooth and not bouncy at all. Ive never had a leaf spring trailer come anywhere close to this ride quality.

Ive only been using it a month so going out west this fall will be the real test, but super impressed so far.

[Rogheff]

I put Timbren axles on my Jeemper but only because the unusual floor design required them. They were xpensive and had to be welded to the frame. Kinda a pain actually. I would've preferred a simple spring axle. Having said all of that, to maintain the walk-in capability of the camper, I'd install them again.

[MickinOz]

I do have one thought about all springs. The heavier they are, the closer you get the point where the axles are effectively bolted straight to the frame with zero give.
With that in mind, I will say my trailer has 600kg leaf springs, and it weighs about 560-570 Kg loaded. Take off the weight of the wheels and axle, and there is probably 540-ish kilos pressing on these springs.
They are ALKO springs, and ALKO rate their springs by how much weight is required to deflect the springs 2 inches, so they can actually carry more than that.
I get to watch the wheels moving up and down in the rear view mirror while the trailer rides steady.

I think a big mistake some people make is to go too heavy on the springing.
Doesn't matter what style of suspension you have that is going to shake sh** out of the trailer, and those suspension parts that can't "give" will eventually bend or break.

[Squigie]

I don't know if I said so before in my old reply, but a lot of trailers also have very little suspension travel.
One of the worst examples that I have seen is, unsurprisingly, one of my own trailers - an open cargo trailer that was modified by a landscaper to the point that it might as well have been home-built.

3,500 lb axle.
~950 lb dry weight.
The leaf springs never sag. They never extend. They never flex. They never move.

Unless I have 2,500+ lb of crap in the trailer (which is difficult to do, as the deck is only ~49"x~95"), at which point they still don't sag but the axle smashes into the frame rails with every bump on the road.
...Because it has less than an inch of clearance between axle and frame, with no bump stops.

It's dumb. It's ugly. It's far from ideal.
And it is pretty normal from what I have seen on trailers - especially cargo trailers.

A couple weeks ago, I was looking at the suspension types and arrangements on some trailers stacked for the winter behind Lowe's, while waiting for someone that was running behind for our lunch meeting.
One of the 4'x8' flatbed cargo trailers had a single 3,500 lb axle, springs that looked too weak for the job, and less than half an inch of possible suspension compression. With the trailer empty, there was less than half an inch between the axle and the frame.
That's a winning combination, right there.