Articulated 4 link rear suspension

[Stan H]

The track bar simply holds the axle centered on the frame. It’s generally neutral at normal ride height, and shifts slightly to either side during articulation.

a triangulated 4 link will hold the axle centered because of the nature of the design…triangles…so the track bar would serve no useful purpose.

Okay #1 there is already a 4 link suspension on the Gladiator.
#2 how does another 4 link suspension with Johnny joints eliminate the track bar ??
#3 There is only 2 bars showing in that kit yet says its a 4 link
#4 It is still held on with bolts that shift and move and loosen. I had a 68 Chevrolet pickup truck that had control arms on the rear and it was held on with Ubolts they moved and wallowed around and wore groves in the axle.
Owned several Fords with leaf springs which had a plate and 2 U-bolts. Always wallowing and breaking and coming loose often requiring double lock nuts and even when ya got them to stay tight they rusted up . I despise U-Bolts in suspension systems . They are old tech and a thing of the past.

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[Stan H]

The truss can be welded to the axle tubes and the u-bolts removed. They actually recommend welding for hard use. Personally I kept the ubolts in place after welding for an extra level of strength. I'll take ubolts and proper suspension geometry over the terrible short upper/long lower factory setup and its resultant wild pinion angle changes.

Then you welding it to the axle tube again not something that can be too easily changed once its done. Welding on axle tubes on my opinion is a high level skill also due to it really messing things up. Obviously you got yours done right . But hmm just ain't for me. I just dont see it .

 

[Zachanadandy]

Then you welding it to the axle tube again not something that can be too easily changed once its done. Welding on axle tubes on my opinion is a high level skill also due to it really messing things up. Obviously you got yours done right . But hmm just ain't for me. I just dont see it .

I think this might be the first time I've seen anyone argue a truss would somehow weaken or compromise the axle. There's some skill involved for sure but unlike a typical weld on truss this one is full bolted in place before you weld. Burn in a section, switch sides, alternate back and forth to minimize the chance of warping anything. And now you have much better rear suspension geometry where the pinion stays pointed in the right direction even if you go to long travel rear shocks, a stronger axle, you've eliminated the chance of spinning a tube. Why would you want to change it? Even if you're one of those wierd owners that holds on to every stock part and plans to waste a bunch of time returning it to stock when you're done with it, just bolt the stock uppers and track bar back in and leave the truss in place.

 

[Stan H]

I think this might be the first time I've seen anyone argue a truss would somehow weaken or compromise the axle. There's some skill involved for sure but unlike a typical weld on truss this one is full bolted in place before you weld. Burn in a section, switch sides, alternate back and forth to minimize the chance of warping anything. And now you have much better rear suspension geometry where the pinion stays pointed in the right direction even if you go to long travel rear shocks, a stronger axle, you've eliminated the chance of spinning a tube. Why would you want to change it? Even if you're one of those wierd owners that holds on to every stock part and plans to waste a bunch of time returning it to stock when you're done with it, just bolt the stock uppers and track bar back in and leave the truss in place.

Well , it is already a 4-link .
I guess I'm the first then. Sorry.

 

[Stan H]

Again what is that truss doing to stop axle shift side to side ?
Both designs attach to the tube ?
How is that any different ?
I just dont get it.

 

[JTGuy]

I can see that the triangulated links are better than the track bar. I can see that the track bar would cause the diff to do some weird stuff when it hits some bumps. Would also cause the body to move more just due to the nature of the track bar mounting. I'll weld it after I check the alignment . Will I need to change the diff oil after welding?

 

[Zachanadandy]

Again what is that truss doing to stop axle shift side to side ?
Both designs attach to the tube ?
How is that any different ?
I just dont get it.

The triangulated links center the axle, not really the truss itself. If you have 4 links running at 90⁰ to the axle you need the 5th horizontal link to keep the axle from moving side to side. There are several drawbacks to this design. The axle is pulled/pushed side to side during suspension movement. The flatter the track bar, the less of an arc it travels in but it still moves side to side. The 2nd drawback is the cross talk between the front and rear track bars. Every bump that causes the front to move passenger causes the rear to move driver and vice versa because they are mounted to opposite sides of the frame. That's what causes the majority of the head toss when you hit a big dip or bump at an angle. With triangulated uppers the rear axle moves straight up and down when the suspension cycles resulting in a much smoother ride. The uppers and lowers being the same length also eliminates the pinion dive you get from the stock suspension helping with wheel hop/axle wrap. The other benefit nobody talks about is spare tire clearance. No need for a bent track bar to clear the spare when you don't need a track bar at all. The 37" MT fit no problem. It looks like a 38 or maybe even a 39 would fit. It's an all around better suspension design.

 

[PuddleJumper]

Well, it's ordered and on sale. $709 delivered to my door. I have spoken the RC and the install should be cake. I'll be selling my Synergy rear TB and the bracket.

Is RC, rough country? RCcrawler? RockKrawler?

 

[PuddleJumper]

The triangulated links center the axle, not really the truss itself. If you have 4 links running at 90⁰ to the axle you need the 5th horizontal link to keep the axle from moving side to side. There are several drawbacks to this design. The axle is pulled/pushed side to side during suspension movement. The flatter the track bar, the less of an arc it travels in but it still moves side to side. The 2nd drawback is the cross talk between the front and rear track bars. Every bump that causes the front to move passenger causes the rear to move driver and vice versa because they are mounted to opposite sides of the frame. That's what causes the majority of the head toss when you hit a big dip or bump at an angle. With triangulated uppers the rear axle moves straight up and down when the suspension cycles resulting in a much smoother ride. The uppers and lowers being the same length also eliminates the pinion dive you get from the stock suspension helping with wheel hop/axle wrap. The other benefit nobody talks about is spare tire clearance. No need for a bent track bar to clear the spare when you don't need a track bar at all. The 37" MT fit no problem. It looks like a 38 or maybe even a 39 would fit. It's an all around better suspension design.

Any impact on towing or handling say 700lbs in bed? I'm finally lifting my Mojave and triangulation kits seem like a killer bang for buck setup.

 

[Zachanadandy]

Any impact on towing or handling say 700lbs in bed? I'm finally lifting my Mojave and triangulation kits seem like a killer bang for buck setup.

700 lbs in the bed is pretty normal fair for us with camping gear and building supplies heading out to our AZ property which is ~540 miles from the house. No issues at all. Even towing beyond the rating at 8200lbs it handled great. Had to get all the lumber, doors, windows, etc out there and it's too far for multiple trips. Almost 500lbs worth of roof shingles loaded up last night. Add camping gear on top of that. Headed out this afternoon.

 

[PuddleJumper]

700 lbs in the bed is pretty normal fair for us with camping gear and building supplies heading out to our AZ property which is ~540 miles from the house. No issues at all. Even towing beyond the rating at 8200lbs it handled great. Had to get all the lumber, doors, windows, etc out there and it's too far for multiple trips.

can you link the kit you got? Your like the only other guy on this forum that i know runs the Mojave pretty hard. and if i dont have to spend MC money to, that'd be great.

 

[Zachanadandy]

can you link the kit you got? Your like the only other guy on this forum that i know runs the Mojave pretty hard. and if i dont have to spend MC money to, that'd be great.

Mines a Hodge podge at this point but the 4 link kit is the same one linked earlier in this thread. https://rockkrawler.com/jt-pro-x-upgrade-kit/
The springs are metalcloak 3.5", so are the front sway bar disconnects, flipped drag link, and raised trackbar bracket. Still running the bump stop spacers, rear sway links, and shock extensions from the original AEV 2" spacer kit. Front control arm drop brackets are EVO as I found a killer deal on a never installed used set on the JL forum. Best shot I have of the front suspension setup.

 

[PuddleJumper]

Mines a Hodge podge at this point but the 4 link kit is the same one linked earlier in this thread. https://rockkrawler.com/jt-pro-x-upgrade-kit/
The springs are metalcloak 3.5", so at the front sway bar disconnects, flipped drag link, and raised trackbar bracket. Still running the bump stop spacers, rear sway links, and shock extensions from the original AEV 2" spacer kit. Front control arm drop brackets are EVO as I found a killer deal on a never instance used set on the JL forum. Best shot I have of the front suspension setup.

thx! I'm prepping for the min lift required to fit a hemi, I got FOX 2.5 ELITE DSC used for dirt cheap. Getting them revalved to match the Factory feel but obv handle my extra weight. I'm using Ironman4x4 2in lift springs as i had good experience with them on my Toyotas and they are the closest to the stock spring feel as i could find but have additional payload rating. (love the aussie rating system personally) I have bump stop ext but i need to replace the front bumps as they are both blown (a few too many jumps lol). So that leaves track bars, but i don't like any of the designs especially for the prices. I want a bar that has OEM style adjustment. Is the MC bracket for your front track bar only good for 3.5? and who makes the flipped draglink kit? I just wanna get this dialed. All in all I'll only be .75" over stock but it should clear everything hemi wise.

 

[VA6489]

Again what is that truss doing to stop axle shift side to side ?
Both designs attach to the tube ?
How is that any different ?
I just dont get it.

Easy visualization Draw three equal lines in the form of a triangle. Two points are the link arm attachments to the frame. The last point is attached to the axle at the center of the diff. Side to side movement is limited by the 2 arms from the frame to the diff center. The arms can't shorten and that single point on the diff is fixed ( No movement side to side). This keeps the rear axle centered. Now that the axle is centered the track bar is no longer required and if left in place will bind the suspension as the track bar will try to move the axle side to side as it goes thru it's travel.

 

[Stan H]

Another question, let's say I decided to go with a bigger lift . And I had this contraption on there how does it affect the axle as the frame moves upwards.

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