Adventure trailer suspension discussion

I will be starting a build thread for a teardrop based expedition trailer, but I am designing the suspension and wanted to see if anybody had any experience.

The trailer will be on 31" for the moment. The axle is a flipped 4" drop axle. Due to the number of ledges on the trails I will be running, I like the idea of a trailing arm type suspension. My idea is to do a trailing arm setup with a single swivel mount up front with arms going back to the wheel area on each side. That way if I drag going over a ledge, it won't be dragging on the frame, but on the arms. I am planning on using airbags and a panhard bar..

I need some short shocks. Anybody have a source? What swivel mount do you recommend up front? I've been thinking about using a large RE SuperJoint.

Comments anybody.

Tom, check out StumpXJ's build in the trailer section of Expo.. since he hasnt copied it here yet.

He built what your describing. My trailer is also a trailing arm design but i'll be using coils for awhile. I dont see a problem using the large RE joints.

Looking fwd to your build.

old_man said:

I will be starting a build thread for a teardrop based expedition trailer, but I am designing the suspension and wanted to see if anybody had any experience.

The trailer will be on 31" for the moment. The axle is a flipped 4" drop axle. Due to the number of ledges on the trails I will be running, I like the idea of a trailing arm type suspension. My idea is to do a trailing arm setup with a single swivel mount up front with arms going back to the wheel area on each side. That way if I drag going over a ledge, it won't be dragging on the frame, but on the arms. I am planning on using airbags and a panhard bar..

I need some short shocks. Anybody have a source? What swivel mount do you recommend up front? I've been thinking about using a large RE SuperJoint.

Comments anybody.

Click to expand...

Yeah also on Portal PM Desilcruiserhead he did a custom set up on a m416 he is here in Utah. He have very in depth write ups on the process there.

OverlandXJ said:

Tom, check out StumpXJ's build in the trailer section of Expo.. since he hasnt copied it here yet.

He built what your describing. My trailer is also a trailing arm design but i'll be using coils for awhile. I dont see a problem using the large RE joints.

Looking fwd to your build.

Click to expand...

In reality, there will be only one RE Joint up front. I'll just use heims for the panhard.

OverlandXJ said:

Expo..

Click to expand...

URL?

XJBANKER said:

Portal

Click to expand...

URL?

:idea:


www.expeditionportal.com

Hi Tom, I dont have a lot of photos while building my suspension, but I can tell you it works amazingly well. I built basically just like you said. I used shocks from a mid seventies checy 1/2 ton truck (new), my dad has one and I realized that the shocks were fairly short.

A word worth mentioning, you may want to re-evaulate the flipped drop axle. I am using a straight axle, with the same set-up you are describing, airbags, trailing arms, panhard etc. I already have 25 inches of ground clearance to the bottom of my frame rails at ride height, and my axle is on TOP of the arms. 24 inches is typically ideal with a Offroad trailer, however, you may need more for your rig... not sure. I am also running Cooper STT's in a 31 inch size. Too high and they get tippy.... Just throwing it out there.

Here is a link to my photobucket page:
http://s114.photobucket.com/albums/n257/topfuel443/Expo%20Trailer%20Build/?start=all

Here is a link to the build thread.

http://www.expeditionportal.com/forum/showthread.php?t=34786

For attachments, I used these, on both ends of the panhard, and the front of the arms. My arms are 1.5 inch square DOM tube, with .25 wall, and are 36 inches long. panhard is 1.5 round DOM, also .25 wall, I basically made it as long as possible.

These are what I used:

http://www.ballisticfabrication.com/Single-poly-bushing-with-DOM-sleeve_p_1197.html

No need to use fancy and expensive heim joints on a trailer.. the tongue is what takes up all the articulation. Think about it.

Good luck!

~ James

Tom, I am looking forward to this build. Have you got plans now? I want to do the same thing. A small tear drop trailer for the kids to sleep in with my roof tent on top for us parental units.

I'm using a single RE Super Joint for the front. Will most likely use poly bushings like you on the panhard. If I can ever get over the flu I will start posting some pix and drawings. My axle is wide enough that if I don't like the flip-drop, I can cut it and make it a straight axle. I'm going to have to narrow it anyway.

Ahh... I missed that little tid bit, you mean like one single joint in the middle, with the two arms angling out to the axle ends. One joint, for both arms? Suppose that will work just fine as well. What is your reasoning for doing it like that as apposed to two separate arms that run straight back from the front. Just curious.

~ James

From what I figure, if a dual arm setup has the arms fixed to the axle by welding or some other nonflexible method, the whole axle becomes somewhat of a sway bar, much like a radius arm setup, but without the flex joints mounting the arms to the axle. It would seem to limit flex.

My configuration can be visualized as a rigid triange. Two of the corners are the wheels, while the third is a multiaxis SuperJoint. Both setups need a panhard.

But the bottom line is that I like to be contrary and do things different. You have to remember I'm an engineer. :laugh3:

Im married to an engineer, I do understand.

I used just regular axle u-bolts to attached the axle to the rear of the arms on mine, with a locator pin similar to whats on a leaf pack. The rubber front bushings, coupled with the non welded attachment at the rear does allow some flex.

However... due to the way a single axle trailer works (like the triangle you mentioned), there is no reason to need what we usually speak of (with Jeeps) in terms of flex/twist or articulation. The rigid triangle suspension you are building is kind of redundant in that sense when you think about it, since the trailer itself is already a triangle. The trailer will always twist/pivot/articulate off of the tongue or coupler, not matter what kind of suspension we use. In essence, your suspension set-up, and my suspension set-up will work exactly the same (mechanically), except you have one [expensive?] joint and I have two bushings.

I think, in talking with offroad trailer manufacturers, the best thing to shoot for in general with trailers is smooth up and down motion and travel, ground clearance, and adjustability for varying loads. The coupler handles the rest.

like bellow....




Looking forward to your build photos, its fun to see all of the different ways of doing stuff!

~ James