Solid Axle Swap - Track Bar Design Question

[WV Native]

I'm posting this here because Jeep guys are pretty knowledgeable regarding suspension design and have lots of experience. My apologies in advance if this is inappropriate to ask on a TJ forum.

I did a leaf spring solid axle swap on my 2010 Colorado and unfortunately have found a need for a track bar. I've read every article in regards to not needing a track bar with leaf springs. I've also read every article as to why track bars don't articulate in accordance with the leaf springs so you don't necessarily need to poke fun at me (I know it's coming though). The YJ forum threads almost always suggest removing track bars.

I'm running front shackles like the YJs and the J series trucks (etc.) used. I'm using Y-link steering with short shackles (3.25 inches hole to hole) and I feel like the axle is shifting enough to create a situation where it is wandering on the road. Lots of vehicles running front shackles also ran track bars but I was hoping not too.

My alignment numbers look pretty good (imho) so I feel the issue could be reduced with a track bar.

Camber is -0.1 Driver and 0.0 Passenger
Caster is 4.9 Driver and 4.2 Passenger
Toe is 0.04 Driver and 0.10 Passenger

I'm having difficulty packaging the track bar because I didn't plan on utilizing one and it wasn't considered during my initial design.

My drag link is 41.25" center to center - My track bar is going to be approx. 39" to 39.5" in length depending on the mount I have to build.

My question:

Can my track bar be higher (vertically from the ground) than my drag link as long as the angle is the same?

I'd like to have the track bar 1-1/2" higher than my drag link on the frame side and then raise the axle side mount the same 1-1/2" to keep them at the same angle.

Does it work that way or will it give me bump steer issues?

Thanks in advance for your much appreciated input.

 

[freedom_in_4low]

Strictly answering your question and disregarding the spring type, yes they can be at different heights as long as both ends are located similarly in relation to each other (ie axle end can be 3" higher and 2" left of the drag link end as long as it's also 3" higher and 2" left at the frame/pitman arm end).

In the larger context of your post, I don't have enough leaf spring experience to know for sure that a track bar is what's in between you and a good handling rig, or if inverted Y is really the right type of steering linkage to begin with. Hopefully someone comes along and chimes in with some wisdom, and bonus if it saves you the work of packaging a track bar into a design that didn't plan for one.

 

[CMBD]

My first thought would be relocate the shackle to the rear of the spring. Have never seen anyone do a SAS and chose to put the shackle in front.

Not exactly the front end setup your working on, but its a solid axle Colorado. Could give you packaging ideas.

Used to ride in to work with Kevin in that when it was stock. Factory 5.3 in a truck that size is cool

https://blog.bds-suspension.com/?cat=767

 

[pc1p]

Despite what some internet, especially some YJ "experts" suggest, a track bar is indeed helpful in keeping a leaf-sprung front axle centered. I was blowing out shackle bushings quite often and noticed that the handling, while okay, was not as good as it could have been. After talking to a lot of old CJ and buggy guys, I ended up putting a track bar on mine after the Dana 44 swap.

The difference in handling was simply amazing - to the point where I almost jumped the curb on the first turn I made in the neighborhood (the steering was that much more responsive!). In a dozen or so off-road outings and trips to the lake, I never blew out another shackle bushing.

I used the Dave's Custom Unlimited bar and bracket. Despite what many YJ guys thought, I never lost any travel or had any issues. I even put up a 550 on the CTI ramp... certainly not "Flexzilla", but for off-the-shelf springs I was more than happy.

When the guy I sold it to took it for a test drive (although it was meant for his son), he said the YJ handled better than his newer pickup truck. My track bar was slightly higher than the drag link (I was running crossover steering on GM flattop knuckles). As long as the draglink and panard bar lengths are close and the angles are close, you should not have any noticeable bumpsteer.

 

[mrblaine]

My question:

Can my track bar be higher (vertically from the ground) than my drag link as long as the angle is the same?

Yes, it isn't as desirable as in the same plane but the minor amount of bump steer is pretty much going to be a non issue since the leafs aren't being controlled very well by the shackles. If they were doing their job correctly, we wouldn't be having this conversation.

I'd like to have the track bar 1-1/2" higher than my drag link on the frame side and then raise the axle side mount the same 1-1/2" to keep them at the same angle.

Should be just fine, keep a close eye on making them parallel and do that through the pivot points, not bar angle.

Does it work that way or will it give me bump steer issues?

In a normal situation, the spring eye bushings and shackle bushings have enough stiffness that steering effort is directed to the knuckles with minimal losses. What you've described is not that. The chassis is wallowing on the springs and needs something to help it behave which is exactly what a trackbar does.

Thanks in advance for your much appreciated input.

Don't thank me, I don't work on leaf sprung rigs.

 

[freedom_in_4low]

Despite what some internet, especially some YJ "experts" suggest, a track bar is indeed helpful in keeping a leaf-sprung front axle centered. I was blowing out shackle bushings quite often and noticed that the handling, while okay, was not as good as it could have been. After talking to a lot of old CJ and buggy guys, I ended up putting a track bar on mine after the Dana 44 swap.

The difference in handling was simply amazing - to the point where I almost jumped the curb on the first turn I made in the neighborhood (the steering was that much more responsive!). In a dozen or so off-road outings and trips to the lake, I never blew out another shackle bushing.

View attachment 377349

View attachment 377351

View attachment 377352

I used the Dave's Custom Unlimited bar and bracket. Despite what many YJ guys thought, I never lost any travel or had any issues. I even put up a 550 on the CTI ramp... certainly not "Flexzilla", but for off-the-shelf springs I was more than happy.
View attachment 377353

When the guy I sold it to took it for a test drive (although it was meant for his son), he said the YJ handled better than his newer pickup truck. My track bar was slightly higher than the drag link (I was running crossover steering on GM flattop knuckles). As long as the draglink and panard bar lengths are close and the angles are close, you should not have any noticeable bumpsteer.

I've never had leaf springs on a front axle so I'm curious about this stuff. Is the trackbar delete one of those cursed mods that the YJ world widely and incorrectly believes in like TJ owners installing inverted T steering and drop pitman arms? I've heard it parroted a lot and on the surface it seems to make sense that the arc of the track bar would bind with the up-down movement of the leaf springs but that doesn't seem to line up with the reality of your experience.

 

[mrblaine]

I've never had leaf springs on a front axle so I'm curious about this stuff. Is the trackbar delete one of those cursed mods that the YJ world widely and incorrectly believes in like TJ owners installing inverted T steering and drop pitman arms? I've heard it parroted a lot and on the surface it seems to make sense that the arc of the track bar would bind with the up-down movement of the leaf springs but that doesn't seem to line up with the reality of your experience.

Most of it has to do with moving away from the stock springs to more flexible versions which tend to lean over under high load steering input or chassis forces. I've been in some very well set up XJ's running 35's with some very flexible rear leaf packs. They need a sway bar when they get that flexible.

 

[WV Native]

Used to ride in to work with Kevin in that when it was stock. Factory 5.3 in a truck that size is cool

Yes it’s cool. Mine has been a labor of love in order to get it where I wanted it.

It’s got a lot of off-road mods that have helped make it a point and shoot wheeler.

 

[WV Native]

Despite what some internet, especially some YJ "experts" suggest, a track bar is indeed helpful in keeping a leaf-sprung front axle centered. I was blowing out shackle bushings quite often and noticed that the handling, while okay, was not as good as it could have been. After talking to a lot of old CJ and buggy guys, I ended up putting a track bar on mine after the Dana 44 swap.

The difference in handling was simply amazing - to the point where I almost jumped the curb on the first turn I made in the neighborhood (the steering was that much more responsive!). In a dozen or so off-road outings and trips to the lake, I never blew out another shackle bushing.

View attachment 377349

View attachment 377351

View attachment 377352

I used the Dave's Custom Unlimited bar and bracket. Despite what many YJ guys thought, I never lost any travel or had any issues. I even put up a 550 on the CTI ramp... certainly not "Flexzilla", but for off-the-shelf springs I was more than happy.
View attachment 377353

When the guy I sold it to took it for a test drive (although it was meant for his son), he said the YJ handled better than his newer pickup truck. My track bar was slightly higher than the drag link (I was running crossover steering on GM flattop knuckles). As long as the draglink and panard bar lengths are close and the angles are close, you should not have any noticeable bumpsteer.

That’s a good looking Jeep. It’s pretty much what I’m shooting for. Mine is exactly the same way…..good but could be better. It’s so close to being right I’m not giving up.

 

[freedom_in_4low]

Yes it’s cool. Mine has been a labor of love in order to get it where I wanted it.

It’s got a lot of off-road mods that have helped make it a point and shoot wheeler.
View attachment 377377

Ok when you said Y link I thought you meant inverted Y...I think you have a recipe for a center dead spot there because the tie rod can roll up and down as the drag link pulls or pushes on it...it has to rotate to the end of what the rod ends will allow before your steering input actually starts moving the knuckle. I would want to address that before designing a track bar into it, because depending on what axle that is you might run a true crossover like a JK or an inverted Y like a TJ.

Note how our drag links run all the way to the passenger knuckle, and the tie rod runs from the drag link to the driver knuckle.

while the later Jeeps also run the drag link all the way to the knuckle, and tie rod runs between knuckles.

 

[WV Native]

Ok when you said Y link I thought you meant inverted Y...I think you have a recipe for a center dead spot there because the tie rod can roll up and down as the drag link pulls or pushes on it...it has to rotate to the end of what the rod ends will allow before your steering input actually starts moving the knuckle. I would want to address that before designing a track bar into it, because depending on what axle that is you might run a true crossover like a JK or an inverted Y like a TJ.

Note how our drag links run all the way to the passenger knuckle, and the tie rod runs from the drag link to the driver knuckle.

View attachment 377379

while the later Jeeps also run the drag link all the way to the knuckle, and tie rod runs between knuckles.
View attachment 377380

I had kinda feared the dead spot as well. I filmed the steering while I turned and didn’t see any evidence of tie rod role but that obviously doesn’t mean it couldn’t be an issue.

I could easily see how much the front leaf spring bushings deflected though. I reinforced and added gussets to the mounts during my build but apparently it was ineffective.

 

[pc1p]

I've never had leaf springs on a front axle so I'm curious about this stuff. Is the trackbar delete one of those cursed mods that the YJ world widely and incorrectly believes in like TJ owners installing inverted T steering and drop pitman arms? I've heard it parroted a lot and on the surface it seems to make sense that the arc of the track bar would bind with the up-down movement of the leaf springs but that doesn't seem to line up with the reality of your experience.

The OEM track bar, which is perfectly fine for factory setups on factory steering, sucks donkey dick with lifted rigs and especially with dropped pitman arms. With lift springs, your track bar mount at the axle end is 2-4" lower than it previously was, which as you noted, follows an arc. As a result, and further droop in the suspension causes the track bar to continue on this arc, which usually hits its binding point fairly quickly, causing poor performance and in many cases, ripping the mounts off the axle or frame. This ultimately leads many to believe that "tRaCk BaRs SuCk!".

I (and others) have found that properly (or as "good as you can get") track bars help handling significantly more than sway bars did (I didn't even run sway bars on my YJ since the lift springs provide plenty of stability). When I did my install, I found a spot that allowed the spring packs to lengthen and shorten as needed, without binding the joints and without hitting anything on the diff or frame. It took a little work but wasn't bad, maybe an afternoon of experimenting (noting here that checking clearances on leaf spring rigs is much harder).

That’s a good looking Jeep. It’s pretty much what I’m shooting for. Mine is exactly the same way…..good but could be better. It’s so close to being right I’m not giving up.

Thanks! She was a good rig...

What axle you running in your Colorado BTW?

 

[WV Native]

What axle you running in your Colorado BTW?

It’s a Dana 44 out of a J20.

 

[freedom_in_4low]

The OEM track bar, which is perfectly fine for factory setups on factory steering, sucks donkey dick with lifted rigs and especially with dropped pitman arms. With lift springs, your track bar mount at the axle end is 2-4" lower than it previously was, which as you noted, follows an arc. As a result, and further droop in the suspension causes the track bar to continue on this arc, which usually hits its binding point fairly quickly, causing poor performance and in many cases, ripping the mounts off the axle or frame. This ultimately leads many to believe that "tRaCk BaRs SuCk!".

I (and others) have found that properly (or as "good as you can get") track bars help handling significantly more than sway bars did (I didn't even run sway bars on my YJ since the lift springs provide plenty of stability). When I did my install, I found a spot that allowed the spring packs to lengthen and shorten as needed, without binding the joints and without hitting anything on the diff or frame. It took a little work but wasn't bad, maybe an afternoon of experimenting (noting here that checking clearances on leaf spring rigs is much harder).

makes perfect sense. I noticed in your photo it looks like the drag link and track bar are perfectly horizontal at ride height.

 

[pc1p]

makes perfect sense. I noticed in your photo it looks like the drag link and track bar are perfectly horizontal at ride height.

They are, and the suspension was just about perfectly centered as well (I think I was using ~9" shocks). For a tractor-motored box-wagon, it worked well off-road.

 

[pc1p]

It’s a Dana 44 out of a J20.

Mighty be worth seeing if you can find some GM flattop knuckles and going with crossover steering. It will help a lot with your potential steering concerns. I believe the FSJ axles all use GM 6-bolt spindles too, so won't be much of a swap really.

 

[RINC]

I need to get back to that spot now my rig has been upgraded.

 

[pc1p]

I need to get back to that spot now my rig has been upgraded.
View attachment 377393

Plus you’ve got a bunch of seat time now!