Question on Dexter Torflex axle (1 Viewer)

[smritte]

One of my friends bought a teardrop trailer with a 2200# torflex axle. Dexter hasn't been much help other then giving me the build sheet from when the axle was ordered. The trailer weight is in the upper range of the axle according to the information Dexter sent me.

Here's my 2 questions
Is it possible to change the spring rate once the axle has been manufactured. (from what I see the answer here is no)
Can you order diffrent spring rates when the axle is manufactured. Dexter wont tell me this.

Without posting everything I've done, the issue is, the axle has way too much spring weight. The trailer is 1600# with a 200# tongue weight. That gives me approximately 700# per axle. unloaded to loaded the axle only moves .5 inch. By my math that means ~ 1400# spring weight each side.

On a small dip the trailer literally bounces 1-2 foot off the ground.

 

[spressomon]

Stamped on the axle tube of the Torflex is a SN which Dexter will be able to provide the build sheet from.

FWIW/FYI, our 2014 Escape 15A fiberglass trailer came with the 3500lb Torflex (later renamed Torfux by me...) was IMHO a total POS. Very limited suspension "travel"...was one of the biggest issues. But the biggest issue arose when the damn thing just locked/froze up.

Jason Reeves aka @trailtailor aka @reevesci removed the Torfux and installed OME 60-Series leaf springs...and Bilstein shocks.

 

[smritte]

Thank you for the reply. As I mentioned above, the build sheet was all I got out of Dexter. That information came the next day. My follow up questions (the same two I listed) have gone unanswered.

Fabrication wise, I've built several trailers over the years. All but one have #3500 axles and leaf's including my current tear drop and M-100. 50 inch leaf's and shocks, those things float through bumps. Oh...shocks are a must.
I cant do that to my friends trailer because it has a weirdly designed aluminum frame with cross members welded under the frame rails. I would literally have to build a frame and attach it to what's there now. So...I don't want him to get a new torflex on the assumption that his is somehow frozen just to be back to square one.

I will confirm the thing you said about limited travel. I've driven behind several trailers over the years with the torsion or the rubber springs (name?). None of them had the travel I would have hoped for in an "off-road" trailer.

 

[smritte]

I thought I would update this with my new information.
Dexter sent me a ton of info but never actually answered any questions about spring rate. I spoke with several trailer shops and...well I'm sure they make great street trailer's by bolting things in. None of this surprises me and doesn't upset me.

Bottom line, the amount of deflection the trailer has is within the parameters of the axle. The trailer is too light. I sat down yesterday and did the math. According to dexter, unloaded to full load, the trailing arm only moves a couple of inch's. Remeasuring more precisely we got about an inch of travel. When you order from them, the axle is built with the intended spring rate. If your trailer is too light, you have no choices. Dropping down in axle size means no brakes and the trailer is too heavy for the axle.

Over my lifetime I have built suspensions for several desert trucks, a couple of long travel rock rigs and several off road trailers. I have traveled with several "bought" off road trailers with the two independents and have not been impressed at all. What I have never done is sit down and actually diagnose or tune one of the independents. As for the trailer in question, I cant easily build him anything due to the chassis is aluminum and the welded the cross braces are below the main frame rails. I would literally need to build a sub frame, which I don't have the time for. Going forward, he needs to run about 10 psi off road to control this.

Not sure if this info will help anyone going forward but understand, if you choose one of the independent suspensions, it will either work or not.

 

[ntsqd]

Our little off-road camp trailer (<2k lbs) has a Torflex under it. Thousand's of US & Baja miles, more than some of them pretty rough, with no issues. It has shocks on it, the guy who built it a new frame (original was not up to the intended use) added some RS9000's to it. Not a stellar choice, but at the time really the only better option was a set of Kuster's, and that just wasn't in the budget or deemed necessary.

Unintentionally I've towed that trailer with only 5 psi in it's then 33-12.50 tires. Tires weren't even mildly warm after ~300 miles of freeway and it rode pretty much the same from what I could see in the mirrors. The trailer now has 31-10.50's on it and I run those at 12 psi everywhere.

Trailers don't need articulation in their suspension (they physically can't) and excessive wheel travel, if it is softly sprung, is a bigger problem than too little wheel travel. The only real advantage to "ITS" is the lack of an axle limiting clearance thru the middle of the trailer. Which I don't think is worth pursuing for the sake of only that. Once you're past not foaming the beer and not breaking the eggs a trailer's ride quality is good enough. Even if you're going to tow it in a NORRA race (like was done in the early days of SCORE), the suspension under a trailer is operating under a very different set of constraints than the vehicle towing it.
Leafs and a live axle work well under a trailer. I'm not a fan, but that doesn't stop me from appreciating them. I think linkage and coils on a live axle are the way to go. Unless you absolutely need to have a consistent ride height regardless of loading. Then you're looking at air springs.