TLDR notice: Traction bars can be a good thing...

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My part of the story:

Before I bought my OUO traction bars I did a lot of research. They were the best bar for my situation and so I jumped at them despite the high cost. I have complete confidence in the bars design based on my real world experience with them and what I learned about them before the purchase. Clay at Riffraff sells them and he has my confidence in everything he sells. He does not sell crap and if there is a problem with one of his products, he addresses it right away.

Despite probably never having to put the suspension into a "full travel" situation, I am willing to bet the OUO bars would do just fine. I remember seeing videos of trucks climbing concrete center dividers like we see on the highway. I remember seeing a fork lift raising one wheel on a truck so high that the truck cab looked like it was going to snap. I remember seeing drive line/suspension before and after videos of trucks without and with traction bars. My mind was made up and for good reason.

I spoke on the phone with Dave at OUO many times and he was a very knowledgeable person. He is actually the one that diagnosed my clutch chatter issue from 2500 miles away over the phone. He arranged for me to see a shop on our route of travel at no cost to us to get an expert he trusted to look at the truck because I was unable to tell him for sure the answers to the questions he was asking. The shop owner called me right away and said I could come by anytime and that Dave was looking forward to hearing what was going on. Dave also called about my steering gear issue just to see how things were going with the repair when it was completely unrelated to his product or services.

Like some others here on the FTE and in this thread, from what I understand OUO is big into racing and the 4x4 community. There are numerous videos out there with OUO equipment being put through torture tests and coming out of it just fine. I don't know how the Pro-Comp bars will fair when compared to the OUO bars, but I don't think that everything out there that is made for the public to purchase is crap. Just because something is not built in a garage by the owner of the vehicle or is not home-brew does not mean it will not satisfy the need of the customer and installer. Not everyone needs a truck suspension that will survive a 10' jump... Not everyone gives a crap about putting the suspension to the extremes of it's design. Most of us use our trucks to drive daily or tow heavy and that is it... There are other companies out there doing a good job with suspension products as well, PMF is another right off the top of my head that creates a great traction bar product for our dinosaurs we call trucks.

OUO YouTube video page for anyone that cares to look further...

 

REPS sent to @pirate4x4_camo .

Separately, it appears that a lot of these aftermarket ladder bar aka traction bar kits call for drilling into the bottom frame flange. Ford strongly and very specifically cautions us not to drill into the horizontal frame flanges. The horizontal frame flanges are the most highly stressed component of the frame, and in the case of these ladder bar kits, the area of the frame where the forward end mounts is under the greatest tensile load. That part of the lower frame flange, in that area of the truck, wants to tear apart, as it is located mid span, in the unsupported bridge distance between axles, under the forward load of the bed, and close to the bed to cab joint, which is where the frame itself resolves torsion inputs that the suspensions did not soak up. Drilling the lower frame flange in that location is ill advised, if Ford, along with every other truck manufacturer whose body builder's manual I have read, are to be believed. Far better to create an L bracket that attaches to the frame in the vertical web, which is the least stressed neutral axis of the frame.

On yet a different note, a few favorable hardware details were impressive in the ProComp kit that @Wes444 installed.

1. Hardened washers, with thick cross sections, and broad bearing surface areas, were provided. Nice.

2. Grade C prevailing torque lock nuts were provided. Nice. Grade C is a great match for Grade 8 bolts, as the Grade C is a little softer than Grade 8, so when the hardware is disassembled, the Grade C nut can be replaced without having to replace the bolt as well, as the thread deformation from the prevailing torque design is all borne by the nut threads, rather than the bolt threads. As it is, the prevailing torque nut hole diameter is ovalized, or distorted, so as to introduce the interference fit that helps prevent the fastener from loosening on it's own from vibration... but as the nut is torqued down, additional distortion from the hardened bolt threads distorts the nut further, "locking" it into place until wrench removed. Once removed, the nut should not be reused, but it is much cheaper to replace the nut than it is to replace both the nut and the hardened bolt.

3. Another cool feature about the locking nut provided is that it is not a Nylock Stop Nut. The problem with Nylocks in underbody applications, and especially with this particular underbody application, where the curbside ladder bar frame mount is located proximal to the exhaust system, is that the plastic in the Nylock melts at elevated temperatures, loosing it's locking powers. No OEM uses Nylocks in under chassis or engine compartment applications, yet many aftermarket kits supply Nylocks, likely because they are cheaper and more readily obtainable than the all metal Grade C Prevailing Torque lock nuts that this ProComp kit provides.

 

take a step back.

I never called either the PC or the ORU bars crap and if it came off that way it was unintentional.

I am not on FTE to judge any companies product or question any users choice or style and certainly do not expect people to use their vehicles as I use mine, nor do I think people need to or should garage build a product over buying retail.

I am here to share my knowledge and love of the 7.3 and SD platform, I just happen to have a lifetime of off road racing and suspension engineering to go with it. If you can take something away from my post, great. If my gibberish doesn’t interest you then thats cool as well.

I went to the effort to measure and document this info simply because it is something I have wondered about for awhile and hopped to foster a technical conversation about exactly what and how these non shackle type anti wrap setups deal with no accommodation for the X axis movement that all leaf spring suspensions have.

 

So just to clear some concerns, I won't be off road racing or rock crawling with this heavy Crew Cab Long bed. Just a daily driver, Lowes runs, 5th wheel towing.

I'll leave the fun stuff to the 71 F100 short bed 4 on tha floor, 360FE motor

 

not many people need to jump their trucks nor is that the point. while you might not care how your suspension does or doesn't work some people do so my question is for those that care I guess.

my video demonstration shows the full suspension range however it is easy enough to extrapolate the data for partial suspension travel to approximate normal daily driving.

ever make a hard right angle turn with a little speed through a intersection ? how about a winding mountain road ? ever hit a small pot hole or god forbid a speed bump with a bit to much speed ?


few people are ever going to bottom out their suspension and use the full travel but I guarantee most everyone uses 1/2 of the travel on a frequent if not constant basis.

if the X axis movement is 1” during 8” of Z axis travel then it stands to reason the X axis would be 1/2” of movement at 4” of Z travel. fair enough ?

Watch a trucks rear axle as they zip through a intersection turning left trying to make a yellow light. it isn’t unreasonable to say there is 4” of travel being used.

going back to my original question.
how are these ( PC and ORU ) type bars accommodating that 1/2” of X axis movement ?

Edit for correction. “X”

something has to be moving, what is it ?

 

Those poly bushings are pretty thick (diameter) it wasn't overly difficult to squueze them in, but more so than rubber ones. I'd ASSume they are what would give a little when needed

 

@pirate4x4_camo , I'll keep my response short and to the point because I know you don't have a lot of time to read extended answers at times.

I do care that my suspension is working properly, just like I care about the rest of the truck working properly. Although, I leave the geometry of the suspension to those people that devote their life to it. Then I pay them for their products and services so I can continue living my life in peace (finally) with my family.



Of course... Two days ago I did this very thing with 12,000 lbs in tow...

Yup! I drove to see SkySkiJason just a couple of weeks ago up Blood Mountain in north GA nonetheless... How about "The Dragon" on US Hwy 129 between NC and TN, been there and done that. I have taken this truck cross country towing heavy for 10's of thousands of miles through 40 states to include the mountains in WA, VA, NC, CO, NV, NM, MT, ID, etc...

Roll over small ones due to tire size, but big ones are always subject to hitting when towing heavy and the safer option is to go through it than around if it time does not permit. Some of the roads we have been on with this truck and 5th wheel trailer remind me of the "roads" I saw and traveled in Iraq, Afghanistan, Pakistan or Saudi Arabia in various war zones. Again, this is all while towing 12,000 lbs at ~65 MPH... Driven through Philadelphia, Seattle, Denver, Chicago, etc...

Speed bumps are there for a reason and I go over them at an appropriate speed for the road or area which typically means rolling over a speed bump. I don't speed much any longer since selling my Audi S4 and retiring.





OK

It is OUO as in One Up Offroad, but I get that you may have misread the acronym I typed out earlier. I wanted to correct the ORU error to make sure the discussion stays on track. I cannot speak for the Pro-Comp bars because I have only seen what Wesley has posted. When we met up this past November in OK near his home, the bars clearly were not installed yet.

Back to your question...

The OUO bars have a semi-rigid bushing at the axle mounting location for the bar. You can see in the image below I took from the internet. This is not the same bar setup I have, this is for a weld on axle mount, but the bushing is the same.



Going off of memory from 3 years ago, I want to say this bushing was about 1.5" in diameter.

Going toward the front of the bar where the front mount is located which I have called a shackle. Your terminology is a lot better than mine when dealing with things like this, so maybe because I called it a shackle I am wrong. I will refer to it as a bracket if you are OK with that?

The bracket holds the bar in place with a large bolt down the center of the bar that also houses an even larger semi-rigid bushing as seen in the image below. You can see a portion of the bushing in front of the bracket and behind the washer and bolt.



In the next image of the bracket looking at it from the rear you can see the back side of the large semi-rigid bushing. I realize semi-rigid is not a very good term to use in order to describe the bushings, but they were compressible to a point by my hand and were not like Energy Suspension polymer bushings in anyway. I would consider them a very tough rubber of some sort. Again, not very good terminology, but I was in the military for 22 years being deployed overseas, not racing across Baja the first part of my life. So, my apologies yet again...



The image below is not an actual picture, but a computerized drawing of some sort so the bushing is not true to scale in relation to the bolt or bracket. This shows how the parts are assembled though and I thought it was worth including to show you how the OUO bars work.


Are we talking Z or X axis based on your question?

You wrote...
Then you wrote...
I believe you may have meant to ask "how are these ( PC and ORU ) type bars accommodating that 1/2” of X axis movement ?", but I will stick with your identification and use of the "Z-axis" question.

So, I hope I have not lost you due to boredom by this point and I have been able to provide suitable answers to your questions regarding the "Z-axis movement" which as I understand it is a vertical motion of the rear axle, the OUO bars allow for movement and articulation of the suspension as designed by Ford. There is more than enough give in the front and rear bushings to allow for ""Z-axis movement" all while keeping the axle from twisting and causing an adverse and less than desirable condition.

If you genuinely mis-wrote and were asking about the "X-axis movement" which as I understand it is the horizontal front and aft motion of the rear axle, the same answer applies which was "the OUO bars allow for movement and articulation of the suspension as designed by Ford."

Do I wish I had the tools, time and talent to design a great traction bar, sure I do. Although, I don't... So, that is why I seek out people that do have the tools, time and talent to design them for me and pay them for their time and talent and use of their tools to keep me going down the road safely and comfortably. Just like the Borg Warner T4/SXE I installed a few months ago, I let others who have devoted their life to developing great products do the work and I pay them so I can reap the benefits of their tireless work and dedication.

Now, if you ever feel like discussing combat/tactical communications support on the ground in third world countries and war zones, well I am your huckleberry... I am now going to take your advice and "take a step back"... You get the last word as I am done mucking up this thread that Wesley worked so hard to put together all while working very hard to earn the promotion he just received and to get his house remodeled. He did this in his "spare" time, which seems like very little lately and I publicly apologize for my portion of straying the content off topic.

@Wes444 , well done on the write-up sir and I look forward to your thoughts on their performance when you get some well deserved time off with the family in the 5th wheel. Maybe one day soon we can meet up again and you can show me the bars in person.

 

@Wes444

when the axle articulates in the Z axis with one wheel going up or down and the other stays the same or in the opposite direction it rolls the bar in the A axis up to 7* or on a 2” wide tube like the bushing holder 1/4”

see how the bushing is tapered ? this is a very clever design that allows the bar to roll over without compressing the bushing.

I can calculate the spring rate (times)the travel and then put the bushing in a press and apply the same pressure. however having done this with other polyurethane bushings I can say without much doubt there is not that much deflection in those polyurethane bushings, i seriously doubt there is that much deflection in even a rubber bushing of the same thickness.

hard to have a perspective in this pic, can you accurately measure the thickness of the inside edge ?

I will guess if the steel sleeve is 3/4 diameter then the thickness of the bushing inside edge ( like where the letter M is ) is maybe maybe 3/8” to 1/2” ?

besides, if those bushings could compress in the Z axis fore and aft then they would also compress in the B axis and allow axle wrap. the whole endeavor would be a moot point other then they would still look cool I suppose.

i am not discounting your theory just dont think it is what is happening. would be cool to set it up and measure it though.

edited for accuracy

 

Well, as Sous mentioned it will be a while before I have enough spare time in daylight to pull a bushing out to measure it, but I'm willing. In theory at least.

 

@Sous good catch, Fixed X

 

Ford designed the suspension ( and drive shaft ) with B axis or axle wrap movement, just saying

Articulation or A axis movement on the OUO is accommodated by the bushing orientation. facing forward/aft as opposed to side to side allows the bar to simply roll inside the bushing, an easy and elegant solution. just happens to be the same way Ford designed the radius arms in the Twin Traction Beam suspension on the 2 wheel drive versions.

The X axis movement is the big question, and the whole point of my posts. EXACTLY HOW does OUO and Procomp allow the axle to move in the X axis ?
those bushing simply do not deflect 1" to be the answer, I certainly do not see 1" of slop in the system so that isn't the answer.

The answer is out there because clearly both bars have not been ripped off the frame, I am looking for the answer as to HOW the 1" of movement that Ford Designed into the suspension is accommodated.

 

No need to take your stuff apart,
I just ordered a M02181 bushing to measure and test the deflection rate. no sense in speculating about it when I can easily just measure it.

 

Is Ford exempt from this rule? Here is my stock frame with plenty of holes in the flange...

 

Berlin eye, in which the wrap persists until the leaf lines up with the pivot bolt. A standard eye would wrap straight off the bottom. A standard eye unrolls and lengthens the main leaf when the spring is compressed, and that moves the axle back. In corners this pushes the outside tire back, which in technical terms is A BAD THING because it means roll-induced oversteer. A Berlin eye moves in a more upward direction in the same circumstances and therefore does not change the axle’s fore-aft position nearly as much. Less roll oversteer is A GOOD THING.



First Gen SD utilized a “standard eye” which increased oversteer/rear steer situations

 

@akcooper9 Please accept my apologies, but I never saw this question put to me back in April, until Mecdac bumped this old thread today.

The answer is no, Ford is not exempt from physical laws and material properties, and Ford is not exempt from engineering principles and best practices that are universally accepted among all truck manufacturers, who all offer the same strongly worded advice to upfitters and second unit body installers, which is "Do Not Drill into the frame flanges".

Proof of the universality of this advisement exists in the Body Builder's manuals of Paccar (Peterbilt & Kenworth), International, Hino, Isuzu, General Motors, Mack, Volvo, Freightliner, and Ford, among others, which all are in agreement offering the same advise very strongly, usually in red, or bold, or all caps, or underlined, or with some other method of emphasis... including "Do Not Drill Frame Flanges" warning stickers on the back of the cab...





On my F-550, with a frame made of 3/8" thick (nominally) steel, rather than the 1/4" thick (nominally) steel of your pickup frame, there are ZERO holes in the frame flanges in the critical back of cab area, which spans between the transmission crossmember location all the way back to just in front of the forward rear leaf spring hangar. This critical area is the center span of the frame bridge between axle supporting points, and has to resolve any planar differences between the front axle plane and the rear axle plane that are not absorbable by the suspension. And this critical span also happens to be where long aftermarket traction bars are anchored to the frame.

Since most pickup truck buyers do not have to worry about vocational beds or bodies to the frame, the label on the back of the cab isn't put on pickups, because there is a factory bed there already. And there is no need to read the Body Builder Advisories if one isn't putting a body on their pickup. Therefore, I only shared the advice from Ford (which is repeated with all other truck manufacturers) because it is not expected to be common knowledge among pickup buyers. That doesn't mean it isn't useful knowledge, and it likewise doesn't mean that it is necessary knowledge, because pickups are not used in the same way as commercial vehicles. The information is there for those who care.

If Ford manufactures their frame with holes in various places, it stands to reason that Ford had the resources to determine that the location and diameter of those holes would not affect the frame reliability or resistance to crack initiation. I don't have those testing and FEA resources, so I keep it simple and follow Ford's advise. To infer that a hole here makes it "ok" to put a hole there is beyond the capability of my guesstimator.