Changing trailer ride height

[dyeager535]

Hey all!

Pretty sure first time posting in here. But here I am.

Got a small utility trailer (4x8 "bed") that I've had in use for the last 10 years or so. Pretty stout for what it is, I know it's had over a ton in it lol, but whoever put it together really got creative. Round tube construction for most of it (black iron pipe I assume, since it's threaded on some ends), and the round tube axle was widened with a section of square tube. We added expanded metal as the deck, along with some support for the expanded metal, and made sides out of metal tube and expanded metal.

The axle was some weird piece, I'm guessing quite old. Couldn't find any seals for it that fit, and I spent a lot of time trying. Bearings started to get bad, so time to replace. Got a 3500lb round tube bowed axle.

I don't want the thing to end up riding higher than it used to. But due to the diameter of the axle tube (and past experience), there isn't enough clearance to run the axle over the springs. That is going to raise the trailer.

Current shackles are 3" long (bolt hole center to bolt hole center) and 2" shackles seem commonly available. My only concern, if that 1" less height would get me close to where I want to be, would be bottoming out the shackle as the trailer was loaded. I'm assuming there is a way to calculate what kind of load would be required to move the shackle through it's arc, but I don't know it.

The previous springs seemed pretty flexy, and on many occasions I had seen them bottom out under load. Having no idea what their rating was, I don't really have a starting point to guess how far these 1750lb springs will react under similar conditions.

At some point I could change tires and possibly wheels to reduce ride height a bit, but it's hard to get reasonably priced tires that small that will stand up to the weight I'd ideally like them to be capable of supporting, even if they never get worked that hard. I'm just worried that a shorter shackle may flatten out and reduce carrying capacity too soon.

Any thoughts on trying a shorter shackle? Realistically it's cheap and easy to reverse if it doesn't work out, but if that didn't work, and I want to keep the same ride height, the only option without redesigning everything, would be to go to shorter tires?

 

[shady]

Is the ride height that big of an issue..? I would think just installing it all and changing your drawbar to a taller one at the hitch, would be the quickest/cheapest way to level it back out.

 

[shady]

Actually if it's a new axle, it should be able over spring anyway.

 

[dyeager535]

Is the ride height that big of an issue..? I would think just installing it all and changing your drawbar to a taller one at the hitch, would be the quickest/cheapest way to level it back out.

Yeah, my rig isn't lifted, and the previous trailer height seems to be the right height for most newer trucks too, so keeping it the same would be nice. I currently don't run any drop on the stinger, so if it went higher, I'd have to flip the stinger. Possible of course, but getting taller also makes it harder to load. Sometimes I run a mower or golf cart up on it, and the angles were shallow enough I don't have to do anything to clear driving them in.

I want to say my frame to axle tube clearance is ~3" with the axle over the springs.

 

[shady]

That should be right. That's what mine are anyway.

Mine are northern tools 3500# axle and spring set. Plus their frame mount/shackle set.
With a 200# load on it on a somewhat potholed road, I never heard it bottom out. It didn't even really seem to set much lower.

And if you flip it axle under, you'll have to put new perches on to keep the bow in the axle UP

 

[dyeager535]

Well I flipped the axle tonight just to test. I had already tack welded the perches on for spring under installation. Obviously with spring over, I gained 3" of height.

It looks ridiculous with 7" of gap between the tire and fender. Dont particularly care how dumb it looks, but as I'm getting older, higher fenders are going to be harder to step up onto. They are welded on good enough I'm not interested in relocating them. The tongue seems to be 2" higher than the ball, I would think with a decent load it would tend to be lower.

You said 200# load. Did you mean 2000? I've never been tempted to load 3500lbs, I really just wanted a safety margin so I knew I wasnt likely to exceed the rating without having to really add up the weights. I can fit 100 gallons of gas, about 80 gallons of water, and 55 gallons of diesel if fully loaded, plus ~5 twenty pound propane tanks, spare tire, and another probably 50 pounds of gear in it, then hit some very potholey logging roads.

Because they ran a spine on this trailer, I've only got two inches of clearance with the axle bow and spring under. I'm not sure that is going to be enough.

 

[shady]

Yeah 2000#... Sorry , missed that.

I've had mine right at a ton a few times now, and except for bumps I'm not even sure it moves the springs down Lol. Doesn't look any lower anyway.

That spine could be an issue.

 

[dyeager535]

I was looking at the spine, I could probably clearance it at least an additional inch with some heat and BFH without worrying about failure under load.

Looks like massive clearance with the axle flipped, but most is gone with the bow and 3" closer.

 

[red EOD]

A simple option would be an axle with a drop in it (4" is a common height, others are available)

 

[dyeager535]

If I hadnt already bought and burned the perches to this one. But absolutely correct. Dang.

 

[red EOD]

Looking at the pics that's about the only option I can think of. Sell the straight axle and get a drop axle instead. The hubs and all that are the same, so you could get away with just buying the axle itself (ebay often has them for a good price). Or post it up on the local classifieds, the 3500 lb axle is commonly used.

 

[shady]

I'd flip it spring under so the bow is up and try it for a while. You can always flip it later if it hits the spine. You'll have to put new perches on to keep the bow up if you run it spring over though

 

[Cili]

Can you go spring under and then just space the spring and shackle hangers down an inch or two?

 

[imiceman44]

If I hadnt already bought and burned the perches to this one. But absolutely correct. Dang.

I would try a longer shackle to give more space for the beam.
Also you could put bump stops so it doesn't hit.

 

[dyeager535]

I was thinking either longer or shorter shackles to depending on spring under vs. Over, but from what I can find, 3" appears to be about the longest, and 2" the shortest. So other than fine tuning, doesnt appear much in the way of significant drop or rise with just shackles.

I was having too much fun welding on the front hangers and didnt just tack weld them. I could get them off, but it would be some work. Luckily the spring perches I did tack weld, so reversal is no issue.

I'm going to hook it up to the truck and see what the ride height is, comparatively. Unloaded, if it has some rake, I dont care. 1-2" additional ride height unloaded may work. With 1500+lbs on it, that would probably sit about right.

 

[dyeager535]

Well, hooked it up to the truck, and while the driveway isn't perfectly flat, it sure looks to me like the trailer sits near level.

I don't have any "before" pics, but pretty sure in the past the reason it looked level was because the weight on the tongue dropped the rear of the truck.

Guess I can't or shouldn't worry about having it sit lower. Deal with it as it is. Now to tear it all back down, knock the tack welds loose and mount the axle properly. Will be nice to get it out of the garage!

 

[imiceman44]

Well, hooked it up to the truck, and while the driveway isn't perfectly flat, it sure looks to me like the trailer sits near level.

I don't have any "before" pics, but pretty sure in the past the reason it looked level was because the weight on the tongue dropped the rear of the truck.

Guess I can't or shouldn't worry about having it sit lower. Deal with it as it is. Now to tear it all back down, knock the tack welds loose and mount the axle properly. Will be nice to get it out of the garage!

It also will change depending on loaded or not

 

[dyeager535]

It also will change depending on loaded or not

Yep. Interested to see what it looks like with 2K sitting on it, but I'm not testing that with tack welds. Although I'm sure the result would be hilarity for anyone fortunate enough to be observing!

Bad enough I was using a block and tackle to flip the trailer over, and the knot keeping the rope attached to the block and tackle failed.

 

[shady]

I've had 2k on mine, with only 3" of free space when empty. And even on the bumpy azz 5 mile trip to the dump, it's never bottomed out. Not a single ding in the paint. So I'd bet 2000 pounds barely moves them springs when just sitting. 1/2"-1" max. Probably not enough to see

 

[dyeager535]

I've had 2k on mine, with only 3" of free space when empty. And even on the bumpy azz 5 mile trip to the dump, it's never bottomed out. Not a single ding in the paint. So I'd bet 2000 pounds barely moves them springs when just sitting. 1/2"-1" max. Probably not enough to see

I kinda figured they would be stiff enough to not squat a whole lot. So far it looks like it's going to sit perfectly if it doesn't squat more than a couple of inches.

On the old one the spring ends would bottom out on the frame under fairly heavy loads, eliminating that is more important than it sitting an inch or two higher.