The Walking Beam Trailer Suspension For Smaller Trailers

Plans are now available for the Twin Torsion Axle Walking Beam Trailer Suspension.  This was introduced on a build early in 2018, with posts about the trailer including a video of the suspension in action.

Walking Beam Trailer Suspension ExampleFor a long time we’ve admired the action and ride control of walking beam style suspensions.  They are mostly on large and very expensive equipment like high-end semi-truck trailers and massive machinery.  They’ve been re-invented many times and are found with all sorts of variations.

This image shows one heavy truck example.

At the same time, we also like the natural damping of rubber and the ride quality found with torsion axles.  They work well as singles, and best in light duty applications.  The hiccup with torsions is they don’t work effectively in tandem or triple.  That begs the question:  Can you combine the benefits of a Walking Beam Trailer Suspension to overcome the load sharing inadequacies of typical Torsion Axles?

The Walking Beam Trailer Suspension

To the question of combining benefits, the answer is YES.  We built it.  We may not be the first, but we engineered this DIY system and built it.  Now many of you have requested blueprints, so we added instructions, and have them in the plans store as a trailer accessory.

Plans are available right now for 2 versions of a twin torsion axle suspension:

  1. Twin Torsions on a Walking Beam SuspensionOur 4K suspension system gives options for a total load capacity of 2000# up to 4200# by using two matching torsion axles.  Use matching axles of 1000# each (for 2000# total); up to 2,100# each (for 4200# total).  Options between, like twin 1500# axles also work.
  2. The beefier 8K version of the walking beam trailer suspension is similar, but with options of 5000# up to 8000# total.  Again, this system uses two matching torsion axles each of half the capacity desired for the total.

Both suspension systems include complete plans and parts detail.  They even have the CAD files needed for the special CNC parts (laser or waterjet cut).

Note:  You can find laser cutting and/or water jet cutting for steel online or locally.  The technology is very common, so most cities have folks that do it.  Do a search and you’ll likely find several possibilities.  Big Blue Saw cut the parts for us.

Please see the images, comments, and walking beam trailer suspension support videos below.  Check out Trailer Axles 101 for more on torsion axle specifications.

Images & Videos Of Construction Technique

For many experienced DIY builders, fabricating with some precision is not a problem.  However, for those that are not as confident, here are some images, comments, and a couple videos to assist.  Look at the things shown — more than just what is explained — for ideas in getting the fabrication perfect.

Matching and aligning the parts left and right is important, so we build everything in matching pairs.

Walking Beam Setup

First up is a video showing the clamping and setup for the main rocker beams.  It’s not long, but it gives tips for precision, the technique, and why.

Certainly, setup is important with suspension so trailer tracking is consistent and stable.  Please take your time while building so the final product will serve you well.

See the blueprints and compare with the images below for the complete product assembly.  That will also show more about the welding intent.

Suspension Pivot Setup

Moving to the frame mounting brackets that support the suspension pivot, these two images show the setup.  The CAD parts show a 1/4″ hole to use for alignment.  That’s it’s only purpose.  Just stick a 1/4″ diameter piece of rod through those holes and the holes in the beams and shims for alignment.

Setting up the frame mount for welding.

Clamp all the pieces as shown.  Oh, and make sure you don’t forget the shim stock between the beam and the laser cut parts.  Those thin spacers are required.

After clamping everything as shown in the above images, remove the 2 big bolts, and clamp that area as shown in the video below.  Add an extra washer or two so there is pressure outward — which will compensate for some of the weld pull.  Get it ready, then weld it all up carefully.  (But don’t weld that pin — it must come out).  Unfortunately, because of the clamps and because of the way they are held  together, you must tack things on the inside first, then unclamp, and weld the outsides.  Weld the insides last.  That will cause weld pull, so watch the next video about solving that problem.

Suspension Pivot Adjustment

This second video shows how to adjust the pivot braces on the frame mount after welding so the walking beam does not pinch while in action on the trailer.  Welding is a ton of fun, but when precision matters, we must compensate for weld pull.

Note 1:  Setup for the frame mount beam is very similar to the rocker beams above.  We suggest aligning all the holes and clamping the two assemblies so everything aligns.

Note 2:  This next video mentions, but does not explain so well — the washers in place prior to welding.  They make the gap extra wide with anticipation of the welds pulling the plates in.  They did pull in, as expected, but more than wanted.  This video shows how to correct the spacing and make it perfect.

I’m not sure if accuracy with the walking beam trailer suspension is more or less important than for other suspension types, but I know for sure that getting it right makes excellent towing.  It’s also pretty easy to achieve by aligning everything in advance of welding, then tweaking things carefully for assembly.  Since the towing experience is the reason for building this in the first place, the videos are here to help.

Here are the final walking beam welded parts set together.  They all fit, including the pivot bolt. The next step is to attach everything to the axles and the frame, then make a test run.

Walking Beam Trailer Suspension Now All Welded And Set Together.

Share Your Experience / Share Your Skill

I’m sure many of you are more skilled in fabrication, so please share if you have added insight.  We’d love to know about better ways.  Please leave comments below, or on the Contact Us page.  Thank you.

For a lot more information about the design and about building the walking beam trailer suspension, please see the post about building the suspension and the Engineering Case Study about the suspension design.

Also, after you complete your build, please share here!  Other readers would love to see your project.  Follow the link to share your story.

Finally, for some more reading, see this other unique trailer suspension.

We wish you the best of luck building your new walking beam trailer suspension.


Inline Feedbacks
View All Comments

We Found These For You . . .

8.5' x 16' 7000 lbs Deck Over Trailer Plans

With a full flat deck, these plans show how to build a workhorse of a deck-over trailer.  Options are plentiful, including ramp sizes, deck types, sides options, rub rails, front rise rail and more.

Solution! for Air Tools
A simple Solutions! reader submission for easy access and organization of his common Air Tools.  Simple enough to build in an hour, and great enough to keep  . . .  forever.  Try this.

Read The Article

Failure -- Trailer Hitch / Unhitch Crash
The trailer hitch and surrounding hardware are OH so important — with safety as the priority.  Here are examples illustrating one success and one horrific failure.

Read The Article

Trailer 5 x 8 - 3500 lbs Torsion Axle

Designed specifically for a Torsion Axle, these 5' x 8' utility trailer plans include a 3500# capacity and many options to choose for making the trailer meet your needs.  And, fully Engineered Blueprints, of course.

Just The Right Size Garage Crane

Get maximum height with a garage crane that still rolls through the door! Use it outdoors, then roll it right in. These Gantry Crane Plans have telescoping legs with options for the beam size and length.

Steel for the Next DIY Build
This is what the beginning of a new DIY build looks like.  Of course, there’s the planning stages, the design stages and finally the acquisition stages where all the raw materials begin to come in.  With all of that behind…

Read The Article

6x14 Utility Trailer Plans

DIY projects designed for you.  These plans show how to construct a 6 ft x 14 ft tandem axle utility trailer with 7000 lb total capacity.  Use the trailer for work or to haul your big toys.

20ft Deck Tiny House Foundation Trailer Plans
There’s an old song comparing the wise man and the foolish man.  It might just be talking about a tiny house foundation!  Goes something like this:

Read The Article

Trailer Suspension Equalizer Link
There are many different sizes and shapes of the suspension equalizer link.  What are they for?  Better yet, when should I choose one shape over another? If you’ve read much on this website, then you know

Read The Article

Review of the Folding Trailer Tongue
On a recent trailer, I experimented with a new folding tongue design.  Now it’s time to review — What do I like?  What would I do different if building another?

Read The Article

20' Deck-Over Trailer

This is our longest 7000 lbs tandem axle deck-over trailer.  These plans are fully engineered and include so many options, because you expect more from plans at Mechanical Elements.

A Unique Trailer Project
There is always something to learn when looking at someone’s DIY project.  This customer story about a unique trailer build is no exception.

Read The Article

What Bolts for DIY?
Bolts are an amazingly simple yet complex fastening method.  They’re used everywhere so mostly we take them for granted, but why are there so many different kinds?  And what bolts should I use?

Read The Article

More Trailer Plans for Torsion Axles
More New Product Announcements:  The Mechanical Elements line of DIY Trailer Blueprints has just expanded – AGAIN – with more trailer plans for torsion axles.  These new trailer plans fill

Read The Article

Finishing or Trailer Frame Painting
(And finishing other DIY Projects.) Now you’ve invested all that time and effort into building an awesome trailer, how should you finish it?   Of course we don’t want it to rust.  And, we want it to last. 

Read The Article

I-Beam Clamp Introduction
Introducing a new product to the Mechanical Elements family of Do-It-Yourself Plans — the gantry crane I-Beam clamp.  A simple product we give as Free Plans in our launch celebration!  Well, is it really FREE Plans?  Yes.  Use the coupon…

Read The Article

What Is The Right Trailer Axle Size?
Some of your Trailer Plans don’t use a standard axle size.  Why not?  Good question, along with the also common “Why should I special order the trailer axle? There are a few common-ish axle sizes that some manufacturers stock. 

Read The Article

Tilt Top Trailer Conversion

Convert our standard Utility Trailer Plans into a Tilt Top Trailer with these Conversion Plans.  It fits our smaller, 3500 lbs, utility trailers in 4' width and 5' width — for both leaf springs and torsion axles.

4 x 8 2000 lb. Torsion Axle Trailer Plans

For a great trailer in the 4 x 8, 2000 lbs size, these plans are a good place to start.  Lots of options bring great function making these Torsion Axle Trailer Plans right for many situations.

16K by 20' Flat Deck Trailer

When heft is on the agenda, consider this beefy version of our 20’ length deck-over trailer plans.  With many options like all our trailers, this tandem axle is super heavy duty for rigorous jobs.