Doing It The Hard Way - JL Steering Box and a Front Stretch

Got my threading die in! That was a total workout cutting those threads, and I had to do it twice! I honestly can't believe the die holder didn't break, I was having a real hard time keeping the part from twisting in the vise.

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Tomorrow I get to cut more chunks out of my frame for the drag link to clear. Both sides!
 
Got my measurements figured out for the track bar and got the order in with IMS for the link to be made. Both my drag link and track bar are 38" pivot to pivot. Wonder how that compares to other TJs with crossover steering setups.

Chunk removed from frame, which will surely get much larger:
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Some slight interference with the radiator. I'll chop that drain barb off, just hoping I won't need more than that. I might, though...

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Here's a full shot of the trackbar mocked up. The bends I made might need some mild tweaking but its close.

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Joint is perfectly level with the drag link joint when steering straight, but offset side to side about.. this much:

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The other end:

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Should clear the spring fine, but will need to notch the frame a little for the trackbar too.

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Joints still clear when turning left because the drag link moves down as that happens:

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If clearance does become an issue, though, I can always mount the joint at an angle so the bolt aims away from the TRE.

Hoping those 3 aluminum links can get here before next weekend 🤞

Pitman arm still needs some more modification. I skimmed about 1/4" off the top face so the joint could sit lower, but I need to take off another 1/4" or so to get it where it needs to be. That doesn't leave much material, so I'll need to reinforce it too. I've got some ideas on how to do that, hopefully it won't take as long as the knuckle did!
 
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If clearance does become an issue, though, I can always mount the joint at an angle so the bolt aims away from the TRE.

Hoping those 3 aluminum links can get here before next weekend 🤞

Pitman arm still needs some more modification. I skimmed about 1/4" off the top face so the joint could sit lower, but I need to take off another 1/4" or so to get it where it needs to be. That doesn't leave much material, so I'll need to reinforce it too. I've got some ideas on how to do that, hopefully it won't take as long as the knuckle did!

Why a JJ style rod end on both ends of the track bar? Might free up some space using a different style on the axle side.
 
Nice work. Takes a lot to get all that to fit and clear.

Thank you, indeed it does!

Why a JJ style rod end on both ends of the track bar? Might free up some space using a different style on the axle side.

If I couldn't make the JJs work I definitely would have just done that, but if I can help it I want joints that take grease and have seals over a standard rod end. The humidity and salty air near the coast in Florida tends to not be nice to bare metal.

I will say though, if my spring perches on the axle weren't as far back as they are with the stretch, there's no way a JJ would work on the axle side unless you were willing to compromise geometry.
 
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I should probably wake this thread up from the dead!
I didn't make much progress over the summer, garage was basically 110° every day, not dealing with that.

Now that it's cooled off, I've started chipping away again. This week I've been trying to figure out the track bar. Surprisingly, this has been the most difficult thing so far to get right, but I think I've gotten it figured out now.

I wanted the track bar to be parallel to the drag link when steering straight ahead and at ride height to give me the best chance of not having bump steer. Due to packaging, it needs to be offset to the driver side a few inches. It of course needs to be equal in length to the drag link as well, which ended up being 38.5". Figuring out how to hold the bar in the exact right position while cycling the steering to check clearance was the difficult part.

Here is what I came up with:

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Using two clamps and four sets of straight edges, and with the axle centered, at ride height, and steered straight, I attached the track bar to the drag link. Then, using two sets of levels and a block of wood, I set the two links level to each other. From there, I basically just eyeballed the side to side position, got the joint as far forward as I could to clear the coil spring, then built the bracket around it. It took a lot of trial and error, cutting and re-tacking pieces in place. All the clamps have to go when I want to test clearance and move the steering. Here is a shot from the front:

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Probably would have been a bit easier if I had gotten a narrower joint, but in the end it worked out, at least I think so.

Here is the finished bracket tacked in. Full lock driver:

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Clears just fine! Full passenger:

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Can't ask for a tighter fit than that!
Clears the tire too, thankfully:

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One issue though is that when the suspension compresses, the bolt head does interfere slightly. It just barely kisses the drag link at full steering stop, and I might be able to fix it with a thinner washer. The one in there is rather thick. If not, a hammer should suffice. This happens because the axle moves forward a little through the arc created by the control arms, but the steering box side of the drag link does not.

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Here is what my steering looks like from the front at a little less than full bump:

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Next task is to figure out the driver side of the track bar mount. Feels good to finally be making progress again!
 
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Discovered a little clearance issue with the spring, so I decided to zip the bracket off and move it outboard 3/8"
Before:
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After:
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I moved it backwards slightly too so the bolt head no longer interferes with the drag link turning right.

Threw the tire on there just to make sure it clears the back side of the rim, which it does. Here is how the tire looks at about full bump:

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Everything actually clears really well, I don't think the fenders will even need to be trimmed.
 
I destroyed my perfectly good pitman arm and turned it into a slightly different one. Ruined the TMR tapered insert when I pressed it out after welding though, replacement should be here Friday.

It's 3x 1/4" plates sandwiched on top of each other, fully welded all around plus rosette welds, all ground smooth. I needed the TRE hole to be higher than the factory one, and didn't feel comfortable bending it.

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I made this part in my 3d printer first but I guess I forgot to take pictures of it. It's a useful tool!
 
Made part of the track bar bracket for the frame end and tacked it on. Really happy to have the track bar rigidly mounted because the axle actually stays put now. It takes a ton of time to carefully set the axle to ride height, make sure it is level, make sure the steering is straight, and make sure the axle is centered with a laser level every single time I move it to check the clearance of something at full bump or whatever.

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It really doesn't stick as far outside of the frame as I thought it might, which will help with the Antirock.

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Tested clearances everywhere at full bump, which is going to be set to 10" of spring length. Hopefully the Currie 4" springs actually compress that much, I'm just trusting some random thread I saw with that info.

Tie rod just clears the joint body at full bump and steering full driver (which brings the driver side of the tie rod up):
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Pitman arm goes into the frame. Cut a little more out than was necessary, not really looking forward to patching that back up and reinforcing it all:
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Axle side track bar joint just barely clears the drag link TRE at full driver turn. Clearance is clearance!
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Bolt head still clears:
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Here is how the bent part of the track bar clears the pitman arm. I may add some gussets to the bar so side loads don't deform it more. There's some room...
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Lastly, the upper link seems to clear the motor mount perch just fine. I've seen other users have issues with this, they must have a ton of up travel.
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Spring seems to clear the link too:
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I think my next task is to tackle the shock towers and mounts.
 
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Mounted my shock in my upper and lower mounts, clamped them to my workbench, then made my own mockup shock out of some scrap pieces of metal shelving. I'm realizing now that I should have used two pieces of round tube that can spin inside each other, but I think I can just twist this metal a little bit easy enough as needed.

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Question for the class - I know Blaine recommends mounting the lower shock bracket basically right up against the outside edge of the LCA bracket. On a normal TJ axle, that seems to be the only place it will fit at all anyways, but on my JK axles, I have a few extra inches to work with. Could I mount the lower brackets further outboard as long as they don't cause the tire to interfere, or should I keep the brackets in the stock position?
 
I made a little sketch in Onshape to help me understand how the shock mounting width at the axle might affect things. These measurements are approximate, but should be close enough to convey what would happen at full articulation.

The 19" dimension is the shock fully compressed, and the 31" dimension is the shock fully extended. The gray dimensions at either side are driven dimensions and are what the effective range of motion would be at the wheels.

Pic 1, shocks mounted vertically, i.e. upper and lower mounting widths are equal:
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Pic 2, axle side mounting width increased 2" per side:
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Pic 3, another 2" added per side:
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Basically it seems like mounting the shocks wider only hurts articulation. Is there anything else I'm not considering? Being able to fit stuff is still going to be the biggest deciding factor I think.
 
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I did some more CAD measurements last night and discovered that really no matter how I package the shock, at least where it will fit, the 12" of shock travel only equates to about 11.3" of spring travel at full articulation. No real surprise there, but after measuring the Currie springs too, those allow up to 13.5" of travel. Because of this, I opted to mount the shock towers as high as I could reasonably get them and kept the axle side of the mounts pretty high up on the axle too. This will give me the option in the future to move to 14" body shocks if I decide I want to, all I'll have to do is move the axle side mount down and out a couple inches and it should net me additional travel.

Here is the shock mocked up at full droop with the brackets tacked in:
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And at full bump:
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An earlier pic with the mockup shock showing the relation to the spring:
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Looks like I have a little issue at full bump with the top shock ears contacting the top cap. I think I'll need to rotate the shock tower backwards a little so that clears a bit better.

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I feel like I'm actually making progress on this thing!
 
I did some more CAD measurements last night and discovered that really no matter how I package the shock, at least where it will fit, the 12" of shock travel only equates to about 11.3" of spring travel at full articulation. No real surprise there, but after measuring the Currie springs too, those allow up to 13.5" of travel. Because of this, I opted to mount the shock towers as high as I could reasonably get them and kept the axle side of the mounts pretty high up on the axle too. This will give me the option in the future to move to 14" body shocks if I decide I want to, all I'll have to do is move the axle side mount down and out a couple inches and it should net me additional travel.

Here is the shock mocked up at full droop with the brackets tacked in:
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And at full bump:
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An earlier pic with the mockup shock showing the relation to the spring:
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Looks like I have a little issue at full bump with the top shock ears contacting the top cap. I think I'll need to rotate the shock tower backwards a little so that clears a bit better.

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I feel like I'm actually making progress on this thing!

Or just grind on the tab a little?
 
Where does the shock sit in the shock tower regarding angle?

At full droop it seems centered, or a tad biases to the front. I would "angle" the tower back so its centered at ride height. That should give you the movement needed without tab to cap interference.
 
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Put a relief in the shock tower to clear the steering shaft joint. Looks purdy now but it took a lot of grinding. Happy with how it turned out.

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Got the position of the shock towers tweaked a bit and I think I'm happy with them now. Only needed to angle the tower back like 4° from where it was before. That caused a big gap between the tower and the spring bucket, so I cut the corner of the bracket out at the front and bent it in a bit to match the new angle. Still a bit of filling that needs to happen at the frame but it should be alright. At least I have a template now and the other side should be more precise.

Full Droop:
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Ride Height:
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Full Bump:
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Clears now at full bump:
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Took the passenger fender off for access. Did feel a bit counter productive:

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Got the other factory shock tower cut off, only smashed my finger with the hammer once..
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Cut out the mirror image of the other Poly shock tower, leaving some extra material where there were gaps on the first side, and got it tacked in with the same angles as the other side. After measuring the top of the tower to the floor and the back of the tower to the front edge of the frame, it looks bang on! Made a tremendous amount of dust today, I really hate having to use cutoff wheels. Probably would have been wise to get a plasma torch before this project started. Too late now I think, I'm too far along.
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Next step is to tack in the lower mounts. I think I want to cycle everything fully with both shocks in before I burn in anything permanently.

Once the shocks are squared away, I want to focus on the front end of the frame. Since I removed so much material from it to clear the links, I'm thinking of just chopping off the frame entirely where it curves down and replacing it with straight box section. Maybe something like the Motobilt front half kit. I don't really have the idea fully ironed out in my head yet. Anything to delete the body lift pucks right? :D