Cargo trailer suspension

[Netter]

Hi,

I been reading about / watching vids /browsing cargo trailers and have a question.
Do these rigs have suspension to "soften" the jostling around a trailer would go thru on these BLM roads? Are they straight axle or are they equipped with leaf springs? That looks like a lot of beating a vehicle takes much less a trailer.

Thanks

 

[tx2sturgis]

Most of them have simple, reliable, leaf springs. Some have rubber torsion suspension. Neither design normally includes shocks, but both designs tend to be 'self-damping' suspensions.

 

[kaBLOOnie Boonster]

Hi,

I been reading about / watching vids /browsing cargo trailers and have a question.
Do these rigs have suspension to "soften" the jostling around a trailer would go thru on these BLM roads? Are they straight axle or are they equipped with leaf springs? That looks like a lot of beating a vehicle takes much less a trailer.

Thanks

Yes of course, most cargo trailers  (bought off the dealer's lot or ordered) have 1) metal leaf springs or, 2) Torflex (rubber knuckle) suspensions; unless you are talking about tiny 4' X 8' cargo trailers. (And I wouldn't know anything about those.)  But if you are talking about trailers big enough to camp in (6' X12' or 7' X 14'), yes of course they have suspensions.

Was confused by your question about "straight" axles.  Straight axles have the same suspension that the industry-standard 4" drop axles have. Straight axles give you more ground clearance. They are usually an aftermarket item or a custom order from the factory.

My trailer came from a dealer's lot with the 4" drop axle-- I immediately replaced it with a straight axle. The leaf springs from the original drop axle worked OK for new straight axle. Or so I thought! They were too light duty, and broke in two years -- thankfully when I was going slowly on a forest road!

So my new leaf springs are rated at 4000 pounds total for a pair, rather than the factory's 3000 pounds for a pair. (The GVWR of the 6' X 12' trailer is 3000 pounds.) So far, so good.

 

[Motrukdriver]

I'm planning on taking the axle completely off of my trailer and installing a timbren suspension system. I'll most likely add a length of 2x2 steel tubing with the ends cut on 45's to lift the trailer up a little. I like the idea of no axle and lots of ground clearance. If my Jeep or 4x4 pickup can clear it there is no problem with the trailer dragging anywhere. Also, I'll be able to match my rims and tires to my tow vehicle instead of having the smaller trailer tires. Here is an example if you don't know what it is. They are made in all different weight ratings, my rig will be small so something like this 3500# would be ideal for me.

https://www.suspensionconnection.com/asr35hds03-timbren-axle-less.html

 

[tx2sturgis]

That looks interesting...the ad copy mentions toe-in and camber adjustments, but I can't see that in the picture unless there is some 'play' in the way the spindles attach to the suspension.

One problem with any of these is toe-in and alignment can be off and cause a LOT of tire wear, so it has to be checked and adjusted if needed.

 

[Motrukdriver]

Yeah, find the straightest pipes you can find and attach them to the rims before you put the tires on then measure width from the front ends of the pipe and then measure the width at the back ends of the pipe. I'd prolly switch the pipes around and do it again just to make sure. Nothing like a shade tree alignment huh??? I have a set of drywall straight edges 8ft long I could probably use. I'll get er' straight.

 

[tx2sturgis]

Not meaning to turn this thread into a trailer alignment thread, but you do normally need some toe-in and you also have to align the axles with the coupler, so there is more to it than just having the wheels perfectly 'straight'.

If the toe-in is correct, but the axle or spindles are not aligned with the coupler's pivot point, the trailer will 'dog-track' and you will still have increased tire wear. 

This picture is for semi-trailer alignment but the principle is the same for a bumper-pull single axle trailer:



A problem I ran into on one of my small trailers is the frame is not perfectly square, and that resulted in a bit of 'dog-tracking' until I measured the amount of 'skew' in the frame and corrected for it. Now my trailer tires are lasting a LOT longer.

 

[Motrukdriver]

Not just lasting longer from wear but safer too because tires that are biting too hard tend to heat up more. Overheated tires are not your friend.

 

[Charly]

Yes of course, most cargo trailers  (bought off the dealer's lot or ordered) have 1) metal leaf springs or, 2) Torflex (rubber knuckle) suspensions; unless you are talking about tiny 4' X 8' cargo trailers. (And I wouldn't know anything about those.)  But if you are talking about trailers big enough to camp in (6' X12' or 7' X 14'), yes of course they have suspensions.

Was confused by your question about "straight" axles.  Straight axles have the same suspension that the industry-standard 4" drop axles have. Straight axles give you more ground clearance. They are usually an aftermarket item or a custom order from the factory.

My trailer came from a dealer's lot with the 4" drop axle-- I immediately replaced it with a straight axle. The leaf springs from the original drop axle worked OK for new straight axle. Or so I thought! They were too light duty, and broke in two years -- thankfully when I was going slowly on a forest road!

So my new leaf springs are rated at 4000 pounds total for a pair, rather than the factory's 3000 pounds for a pair. (The GVWR of the 6' X 12' trailer is 3000 pounds.) So far, so good.

Got a link to the springs you bought?

 

[kaBLOOnie Boonster]

Got a link to the springs you bought?

I am afraid to be hijacking the thread by talking about springs. When the original posted asked about "suspensions", I took him literally and tried to answer his question. Perhaps he really meant "shock absorbers", which is quite a different matter.

Anyway, about the link to springs. There is nothing special about the leaf springs I had installed at a trailer repair shop ("AAA Trailers" in Silver City, NM). It's just that they were rated for 2000 pounds apiece, instead of 1500 pounds apiece, which is what the trailer originally came with.

You could go to etrailer.com and see springs with different ratings.

 

[Charly]

I am afraid to be hijacking the thread by talking about springs. When the original posted asked about "suspensions", I took him literally and tried to answer his question. Perhaps he really meant "shock absorbers", which is quite a different matter.

Anyway, about the link to springs. There is nothing special about the leaf springs I had installed at a trailer repair shop ("AAA Trailers" in Silver City, NM). It's just that they were rated for 2000 pounds apiece, instead of 1500 pounds apiece, which is what the trailer originally came with.

You could go to etrailer.com and see springs with different ratings.

springs are definitely part of a suspension. thanks.