NoNi Rogue

Hey all,

I just recently purchased a set of new 78-79 Ford High Pinion Dana 60 Front and rear axles.

I have a few more months on my Deployment (US Army serving in Iraq.) So all I can do now is some online shopping and some research.

The end result will be full-width Dana 60's, 5.38 gears w/ARB lockers, a Custom 4 link double triangulated rear with an 8" stretch, and a 3 link front. The Jeep will have approx. 6" suspension lift, and 40" tires.

It's a big project, and I plan on posting the build on this thread!

I'm aware of what I'm getting into. I've literally been researching for months.

I have a 4 link calculator and I need some help plugging in the numbers. As I'm not physically near my JK right now, I'd like to get some figures from these forums.

Measurements needed:
- Frame rail mounting points. (Inside width between the framerails at the end of the transfer case rear output. Also, measurment from the ground to the lowest and highest point on the actual frame rail)
- Center of Gravity (From top center bolt of bellhousing to the ground on a stock JK. If the JK has been lifted, please tell me how much lift and what size tires.)
- Rear Axle Lower mounting points. (This will be tough - but does anyone know the width of the rear Dana 60's axle from inside of the mounting surfaces?)

I know that this is not easily done without being under my Jeep. I was just hoping to play around and get a rough estimate of what I'll be getting into.

Thanks all!

Before: (4" Rough country lift on 35" MT's.)


- J. "Jon" Rogue

NoNi Rogue

Hey all.

This is what I have so far. Everything is a guesstimate. Can anyone provide some hard numbers or feedback?


(May need to click to view at full size.)

- J. "Jon" Rogue

NoNi Rogue

With a lot of the 4 link writeups I've seen, I'm told that the forward point of the roll axis (The Forward Lateral Constraint Point) needs to be forward of the transmission (By widening the seperation of the lower control arms at the frame side.) I don't think I've ever seen it done on a true double-triangulated.

As much as I've toyed with this, it seems nearly impossible to get the LCP that far forward without adversely affecting the roll axis, and keeping the angular separation of the upper and lower control arms at the axle.

Any suggestions? - Or, do I not need to worry about the forward LCP?
Are my control arms going to be too long? As of right now, the lower is at approx. 49". I'll be sure to use the proper DOM tubing - but what are my limits?

x No Compromise Offroad x

i have pix I can share, any questions feel free to ask, nice to see another 2 door going this direction ...are you planning to stretch the front any?

When I'm up at the shop again I'll see what measurements I can come up with

NoNi Rogue

I've seen that build in a few different threads. It's the "Krutch" right?

If I were to pick a favorite JK build - yours would be it, hands down. In fact, I've got a lot of inspiration from your build.

For example - If I remember correctly, the top bar of your crossmember is stock, right? I'll likely do something very similar.

After seeing your front stretch, I'm considering doing the same, but running hydro-assist instead of full hydro.

I'll be building in stages, though. I might just have to settle with moving the steering box up for now.

I'll be watching your build very closely. I'll likely pick your brain a lot, as I'm hoping for a very similar setup.

Thanks for the reply!

- J. "Jon" Rogue

brickman37

I have 4-linked mine, triangulated rear, with coils and shocks, 3-link with pan hard front with coilovers. It crawles great, and I couldnt be happier with it. Good luck with your build.

Screamin Lizard Customs

I've heard there are some slight down falls to the double triangle. It can make the rear end less stable, imagine using a set of leaf springs instead. Plus, who wants the lower control arm mounts hanging so low under the drive shaft.
I saw a Jimmy's buggy at the King of the Hammers with the same set up, they were going up back door, when the entire mount twisted up into the belly. It was ugly!! I'd move the lowers out to the frame rails for a stronger, more clearance, and better stance. Just my thoughts.

NoNi Rogue

I can see why you might think that, but I'm afraid your solution would present quite the opposite result.

Running parallel lowers would decrease stability. Geometrically speaking, a triangle is the most structurally sound. Equilateral triangles (45 degrees at each angle) are the most structurally sound triangles.

This may be a bit wordy - but here's the logic: The angles of the arms at the lateral constraint points of the upper and lower bars (The imaginary point in space where the bars would meet if they were infinitely long) must combine to be at LEAST 45 degrees. Ninety degrees is the most structurally sound, but then one has to also factor in the affects on the roll axis.

Single Triangulated with parallel lowers may provide some clearance, but one would need a track bar to minimize bump steer. That, in turn adversely affects articulation.

Layman's terms: Double triangulated (theoretically) provides sufficient stability and butt loads of articulation. It just has to be dialed in right, hence this thread.

I'm going to tackle this project taking into consideration as much advice as everyone is willing to give me. I'm aware that the practical application of the setup will require many compromises, and I'm willing to make them.

I love the feedback though - I need all the constructive criticism I can get before I dive into this.

brickman37

The lowers on mine do go out to the frame rails, and I do not notice any decrease in articulation.

x No Compromise Offroad x

Always open to some brain picking



compared too......

it wouldn't be a "significant" loss to where you would say "this set up SUX"...you would just notice the improvements if it were double tri

then their crossmember/lower control arm brackets weren't strong enough...many of the racers at KOH had fires due to electrical problems and bad tranny fluid line placement...but do we say "lets do away with tranny's and electricity"?...no...thats an extreme out look but all I'm getting at is just because something broke on a rig at KOH, the most EXTREME race in the offroad world, doesn't make it bad...everyone knows shit breaks, and if it's gonna break anywhere it's a KOH lol

I am more interested in what you've "heard" about a double triangulated 4 link being "less stable" and how you are even slightly comparing it to leaf springs (if I read that correctly ) I don't have to restate what the OP said about the shear mathematics of the set-up, but to add there is also perfect axle location, so the pinion stays on point during articulation

high jack over