Fresh idea - Traction Bars

Ghostman

Ghostman

24v crazy
So I have this idea for some traction bars that is pretty fresh I think. As we can all agree that on a leaf spring suspension setup the axle moves up and down in along an elliptical line. As the axle moves up the springs lengthen and the shackle moves rearward and as the axle droops the shackle moves forward and springs get shorter.

So therefore any 2 bar traction setup with fixed mounting points will have inherent bind on suspension components unless it follows the same arc as the axle which is practically impossible.

I know if you run them long and flat it helps and most people don't complain much and yes the probably cause less bind than what axle wrap causes but I'm just had an idea I thought might work.

Don't mention the ladder bar setup either with a swing shackle because it causes pinion rotation as well.

So here's my thought. Make the bars long and flat like usual. Have a fixed mounting point on the axle side. Now on the frame side use a type of bushing out of uhmw material and capture it in a slide similar to what leaf spring sliders look like. At ride height you would adjust it to where the bar is bottomed out forward, as in it cannot slide forward. But it would have the option to slide back a couple inches when the axle travels up and down.

Any smart suspension guys out there think this would work?


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I think you would want the front point in the middle of the slider at ride height, or else it will bind when drooping.

But experimenting with a new idea is what makes it enjoyable.
 
I wish I knew how much the axle moved forward and backward. I guess I can get out my jacks....


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So instead of a floating leaf spring setup where the springs can moved in the mount on the axle:

The bars float and can move on the frame side?
 
I see no reason why it wouldn't work well. I honestly don't bind with my setup, but I don't have a lot of travel

For setting them up having a lift, and the bars set up on the axle side. With the truck fully drooped out mark where the eye is then do whatever it takes to fully compress the suspension (hydraulic jack maybe) until the frame rises off that arm and mark where the eye is again
 
It'd be a pretty hard hit if the suspension unloads/loads under power.

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What you're describing is essentially the same as what you get with a set of Glacier Diesel traction bars, slightly different motion at the frame end due to the sliders moving along a straight line as opposed to swinging in a pendulum motion, however I feel you'd likely be better off with the pendulum swing at the frame end as opposed to a straight line being that with the sliders, it's actually preferable in an application such as this where you're looking to gain traction (unlike when used on a rock crawler for extra travel) that the sliders are mounted at an angle rather than completely horizontal.

When you mount them at the rear of the leafs in a traditional manner, you want to mount them to where they have a slight incline towards the rear bumper with them centered to where you have say 2" of travel forward and 4" rear (using a 6" slider) It's also beneficial to move the axle forward on the leafs to shorten the lever applied by the front half of the leaf pack as it will help to plant the tires firmer on launch.

Forgive the somewhat crude example but you'll get the idea:

If stock looks like so ____o____

Then what you want to do is re drill the centering pin location on the leafs forward one hole to where it would now look like so: _____o___

What is also beneficial at this point is to run more leafs in front of the axle by cutting the upper leafs to where they run forward from the spring perch, to as close as you can get them to the eye of the front mounting point (add them on bottom instead of top), then simply run a single leaf from the spring perch towards the rear slider so that you now have a softer (and essentially more flexible) spring rate. The rest of the tuning from there is all in your shock adjustments.

By moving the axle forward +/- 2" and stiffening the front half by adding the additional leafs, you now have the essential effects of ladder bars, with the added benefit of the sliders providing a more uniform motion reducing pinion angle change along the arch of the suspension travel.

All of this above comes from either my extensive research of using sliders in a drag racing application or from advice/information supplied to me by those who have used them either currently or in the past, so while I have not run them this way due to my decision to go to 4-link, this is how I would run them if I were to continue running leafs.

Also if I missed something or anything didn't make sense the way I wrote it, feel free to ask and I'll try to clarify or correct where needed based on what I do know or was told.
 
Ghostman said:
So I have this idea for some traction bars that is pretty fresh I think. As we can all agree that on a leaf spring suspension setup the axle moves up and down in along an elliptical line. As the axle moves up the springs lengthen and the shackle moves rearward and as the axle droops the shackle moves forward and springs get shorter.

So therefore any 2 bar traction setup with fixed mounting points will have inherent bind on suspension components unless it follows the same arc as the axle which is practically impossible.

I know if you run them long and flat it helps and most people don't complain much and yes the probably cause less bind than what axle wrap causes but I'm just had an idea I thought might work.

Don't mention the ladder bar setup either with a swing shackle because it causes pinion rotation as well.

So here's my thought. Make the bars long and flat like usual. Have a fixed mounting point on the axle side. Now on the frame side use a type of bushing out of uhmw material and capture it in a slide similar to what leaf spring sliders look like. At ride height you would adjust it to where the bar is bottomed out forward, as in it cannot slide forward. But it would have the option to slide back a couple inches when the axle travels up and down.

Any smart suspension guys out there think this would work?


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Click to expand...

Seems like it would work without binding, but would it be strong enough to not rip it out of the slider and let the bar hit the ground?

Wouldn't it be very similar to using a swing shackle on the frame mount?
 
adamsmarshall said:
What you're describing is essentially the same as what you get with a set of Glacier Diesel traction bars, slightly different motion at the frame end due to the sliders moving along a straight line as opposed to swinging in a pendulum motion, however I feel you'd likely be better off with the pendulum swing at the frame end as opposed to a straight line being that with the sliders, it's actually preferable in an application such as this where you're looking to gain traction (unlike when used on a rock crawler for extra travel) that the sliders are mounted at an angle rather than completely horizontal.

When you mount them at the rear of the leafs in a traditional manner, you want to mount them to where they have a slight incline towards the rear bumper with them centered to where you have say 2" of travel forward and 4" rear (using a 6" slider) It's also beneficial to move the axle forward on the leafs to shorten the lever applied by the front half of the leaf pack as it will help to plant the tires firmer on launch.

Forgive the somewhat crude example but you'll get the idea:

If stock looks like so ____o____

Then what you want to do is re drill the centering pin location on the leafs forward one hole to where it would now look like so: _____o___

What is also beneficial at this point is to run more leafs in front of the axle by cutting the upper leafs to where they run forward from the spring perch, to as close as you can get them to the eye of the front mounting point (add them on bottom instead of top), then simply run a single leaf from the spring perch towards the rear slider so that you now have a softer (and essentially more flexible) spring rate. The rest of the tuning from there is all in your shock adjustments.

By moving the axle forward +/- 2" and stiffening the front half by adding the additional leafs, you now have the essential effects of ladder bars, with the added benefit of the sliders providing a more uniform motion reducing pinion angle change along the arch of the suspension travel.

All of this above comes from either my extensive research of using sliders in a drag racing application or from advice/information supplied to me by those who have used them either currently or in the past, so while I have not run them this way due to my decision to go to 4-link, this is how I would run them if I were to continue running leafs.

Also if I missed something or anything didn't make sense the way I wrote it, feel free to ask and I'll try to clarify or correct where needed based on what I do know or was told.
Click to expand...

UHHHHHH WUT?






















Had to. Good explanation though!
 
adamsmarshall said:
What you're describing is essentially the same as what you get with a set of Glacier Diesel traction bars, slightly different motion at the frame end due to the sliders moving along a straight line as opposed to swinging in a pendulum motion, however I feel you'd likely be better off with the pendulum swing at the frame end as opposed to a straight line being that with the sliders, it's actually preferable in an application such as this where you're looking to gain traction (unlike when used on a rock crawler for extra travel) that the sliders are mounted at an angle rather than completely horizontal.

When you mount them at the rear of the leafs in a traditional manner, you want to mount them to where they have a slight incline towards the rear bumper with them centered to where you have say 2" of travel forward and 4" rear (using a 6" slider) It's also beneficial to move the axle forward on the leafs to shorten the lever applied by the front half of the leaf pack as it will help to plant the tires firmer on launch.

Forgive the somewhat crude example but you'll get the idea:

If stock looks like so ____o____

Then what you want to do is re drill the centering pin location on the leafs forward one hole to where it would now look like so: _____o___

What is also beneficial at this point is to run more leafs in front of the axle by cutting the upper leafs to where they run forward from the spring perch, to as close as you can get them to the eye of the front mounting point (add them on bottom instead of top), then simply run a single leaf from the spring perch towards the rear slider so that you now have a softer (and essentially more flexible) spring rate. The rest of the tuning from there is all in your shock adjustments.

By moving the axle forward +/- 2" and stiffening the front half by adding the additional leafs, you now have the essential effects of ladder bars, with the added benefit of the sliders providing a more uniform motion reducing pinion angle change along the arch of the suspension travel.

All of this above comes from either my extensive research of using sliders in a drag racing application or from advice/information supplied to me by those who have used them either currently or in the past, so while I have not run them this way due to my decision to go to 4-link, this is how I would run them if I were to continue running leafs.

Also if I missed something or anything didn't make sense the way I wrote it, feel free to ask and I'll try to clarify or correct where needed based on what I do know or was told.
Click to expand...

I think you lost me.... :what:
 
uploadfromtaptalk1447859565854.jpg

This, forward or rear of the axle?
I've seen this or conceived of it in my offroading days.



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Last edited:
Is the benefit of the slider on the traction bar that it eliminates the slight arc that a shackled traction bar would add to the pinion during travel? This seems like an overly complicated setup for a very minute problem if what I'm thinking is true.
 
Tate said:
Is the benefit of the slider on the traction bar that it eliminates the slight arc that a shackled traction bar would add to the pinion during travel? This seems like an overly complicated setup for a very minute problem if what I'm thinking is true.
Click to expand...

Basically. Yes, the shackle type that use two bars will rotate the pinion.


My reason is I have seen/heard or people breaking leafs, busting plug welds out, etc from using fixed mount traction bars with leafs.
 
adamsmarshall said:
Where did I lose you? I'll try to explain it in a different/better way if I know where you're lost.
Click to expand...

I guess once you started talking about moving the axle forward or something and only putting springs on the front half of the pack or something lol.... sorry :doh:
 
Ghostman said:
I guess once you started talking about moving the axle forward or something and only putting springs on the front half of the pack or something lol.... sorry :doh:
Click to expand...

I typed almost all my reply up and right as I was about to his reply my stupid laptop decided it was time to update and restart, so lets try this one more time shall we...

So as far as the moving the axle forward part goes, that's simply an option to increase the hit to the tires, not necessary, but does help.

As far as the leaf packs go, while I'm sure you understand how leafs work, I'm going to explain it simply to help explain why they're being rearranged. Your main (longest) leaf is the highest lowest (softest) and the rest of the leafs slowly gains rate as you sink lower in the pack. The factory pack is designed more for comfort and load carrying ability than it is performance, that's why the lower leafs progressively get shorter. As the suspension is loaded, the softer rate flexes until it encounters further resistance against the lower leaf and so forth. All rear leaf spring setup pivot from the front mount, leading to reason why the shackle is on the rear and not the front, that's also why if you look closely, the lower leafs are spaced at different intervals behind the axles versus in front of the axle creating more flex behind.

By moving the lower leafs forward in the pack until they are as close as you can get them to the wrap, you have now essentially created and very high rate (stiff) leaf, by removing all but the main leaf behind the axle, you now have a very low rate.

The slider simply acts as a more predictable and constant shackle, by sliding as opposed to swinging, you now have a more linear range to base your pinion adjustment angles off of rather than a second curve. You also have a more constant spring rate because due to the pendulum motion of the shackle, your spring rate is constantly changing throughout the suspension cycle.

So now you end up with a higher constant front lever (like a ladder bar with a little flex) and a soft spring rate which is now MUCH more constant due to the slider. Now when you launch, the soft rate will allow the suspension to move more freely creating a harder hit, you have also reduced the amount of rebound due to the softer rate allowing the suspension to maintain a more healthy amount of squat until you are on top of the tire.

All you have to do at that point is find a neutral starting point in your shock settings make a few test hits so that you now have a control, adjust the rebound and compression on your shocks, make a few more test hits, and so on until you find the sweet spot.
 
Ghostman said:
Basically. Yes, the shackle type that use two bars will rotate the pinion.


My reason is I have seen/heard or people breaking leafs, busting plug welds out, etc from using fixed mount traction bars with leafs.
Click to expand...

You're going to have pinion rotation with the slider too, though. Just maybe a hair less than with the shackled bars. Especially if the shackle is of a decent length, it will be negligible.
 
Tate said:
You're going to have pinion rotation with the slider too, though. Just maybe a hair less than with the shackled bars. Especially if the shackle is of a decent length, it will be negligible.
Click to expand...

Correct, but because of the way the slider moves along a constant as opposed to an arc, as well as the advantage of having a much more consistent spring rate, you're better off all said and done with the slider.

The biggest kicker here is the time involved installing the sliders due to the measuring and welding involved, but by comparison based purely on cost, you're looking at spending about the same, if not less assuming you can weld it yourself versus building or buying traction bars at $500+
 
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