Stretched TJK (bigger rubber & extra inches)

sierradmax

TJ Addict
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It's been well over a year now since I cut apart a set of axles and got them into rolling axle assemblies. I've finally had some time to share my build and post. I'm at a point now where I need to start asking questions and I know there's alot of good advice that stems from this forum. First up are my axle builds.

Front Axle: JK Rubicon Dana 44
  1. Factory E-locker with micro polished & Heat treated internals
  2. 5.13 gears also polished & treated
  3. RCV's
  4. Rancho high steer knuckles
  5. A.I.O.'s Balljoint deletes
  6. Axle tubes cut & turned for increased D.O.S. Sleeved with 3" DOM.
  7. Clayton Truss
  8. C-gussets
  9. Crown BBK
Rear Axle: JK Rubicon Dana 44
  1. Factory E-locker with micro polished & Heat treated internals
  2. 5.13 gears also polished & treated
  3. Yukon chromoly Shafts
  4. Barnes 4wd axle truss
  5. JLU rear rotors & calipers
I noticed most aftermarket front JK Dana 44 axles come with 10 degrees of separation (D.O.S.). I measured transfer case output, pinion U-joint, axle housing dimensions and came up with 14 D.O.S. which should place pinion parallel or a degree pointed above driveshaft angle.

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Next up is getting the front axle under the rig to see the conflicts. Trying to get as much up travel and as much front stretch as possible had me cutting, adding and pulling the axle in and out from the rig multiple times. Keeping an artec frame side track bar mount limited up-travel and kept my wheelbase at 93.5". It had to go. Also, with high steer knuckles, the drag link would hit the tie-rod using the factory TJ Pitman arm.

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It's been well over a year now since I cut apart a set of axles and got them into rolling axle assemblies. I've finally had some time to share my build and post. I'm at a point now where I need to start asking questions and I know there's alot of good advice that stems from this forum. First up are my axle builds.

Front Axle: JK Rubicon Dana 44
  1. Factory E-locker with micro polished & Heat treated internals
  2. 5.13 gears also polished & treated
  3. RCV's
  4. Rancho high steer knuckles
  5. A.I.O.'s Balljoint deletes
  6. Axle tubes cut & turned for increased D.O.S. Sleeved with 3" DOM.
  7. Clayton Truss
  8. C-gussets
  9. Crown BBK
Rear Axle: JK Rubicon Dana 44
  1. Factory E-locker with micro polished & Heat treated internals
  2. 5.13 gears also polished & treated
  3. Yukon chromoly Shafts
  4. Barnes 4wd axle truss
  5. JLU rear rotors & calipers
I noticed most aftermarket front JK Dana 44 axles come with 10 degrees of separation (D.O.S.). I measured transfer case output, pinion U-joint, axle housing dimensions and came up with 14 D.O.S. which should place pinion parallel or a degree pointed above driveshaft angle.

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Stoked to see your build thread, been following a little from your comments in other threads. Nicely done on the clock and turn. Can you explain how you did the sleeve? Did you put the housing tubes on a lathe? How was the fit putting the tubes on? Did you check alignment post welding? Did you make the alignment/setup bar? How did you account for the blade thickness on the tube cut? Would've loved to see you put 60 C's on the axle and be the first hybrid 44/60 guinea pig here.
 
I should have taken more pictures as I built the axles and I should have machined the tubes/DOM. I used 3", 1/4" wall DOM tube for the sleeves. I purchased a McMastercarr tight tolerance aluminum bar as an alignment bar and machined some pucks to check both the front and rear axle. Front axle had a little bend to it but nothing a couple of carefully placed rosette welds and the chain/bottle jack technique didn't fix. As for the driver side, I pressed on the sleeve as pictured but I made the mistake of not de-burring the sleeve and it took quite a few ugga-dugga's to get it to fully seat.

I was able to press the drivers-outer tube w/ axle C in my shop press, carefully checking DOS every 1/2" to make sure it was going in straight. It maintained same degree until fully seated. The passenger side was the Bitc#. It twisted on me to end up being 1 degree off from the drivers side. A 4" relief cut in the sleeve, the axle clamped on a table and a long piece of pipe welded to the axle C gave me the leverage to get it matching the other side. After I slowly welded, the axle stayed true with the alignment bar.

Both axles, I used the chain/bottle technique when I burned in the trusses.

I thought about the 44/60 hybrid but I'm hopeful these axles will hold up to 37's. I'm just wondering if the 1310 U-joint decision was a good one or not.
 
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So, I haven't mentioned what my goal is..

Mid-arm 3-link front, 4-link rear @ 102" wheelbase on 37's. 21" frame height with 12" front & 14" rear coilovers.

My first obstacle was to address the pitman arm and track bar mount. I read where JK axles benefit from 6" of steering throw while the TJ pitman arm/steering box is 5.5". Some people who've done the JK into TJ axle swaps don't have to change, others say they do..I never measured TJ steering throw but I knew I needed a new pitman arm nonetheless. I had a custom flat pitman arm drilled to 5.75" centers with a JK TRE taper. An outside the frame track bar mount took care of truss contact.

Using the 3-link calculator, some field measurement, and CAD, I came up with control arm mounting locations using 28" control arms. I've decided to use Metalcloak Duroflex joints for the LCA's and Johnny Joints for the UCA. On the frame, Ballistic fabrication Frame link mounts will be used for lowers and Dave Kispaugh's mount used for the upper. At the axle, a single artec link mount shaved down for the upper and I fabricated my own mounts for the axle. I could not find a 10 degree mount placing link below axle Centerline.

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With control arm mounts tacked in place, 1-1/4" PVC mock-up links to 28"+/-, I dropped the axle to ride height, attached the drag link and started working on an axle side track bar mount. Anyone guess what I'm using to mock up as a track bar?

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Last edited:
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Another obstacle.. right side full stuff, drag link and track bar contact the bottom of the frame. I don't suspect this is an issue with factory JK knuckles. It's limiting another 2-1/4" of up travel. Solution, notch the frame..

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Frame notched, Tire rubbing on fender and drag link has just enough clearance to lower radiator. Left side full stuff, differential cover has about 3/16" clearance to the track bar. In terms of a forward stretch, I netted 2.5". With the flattened pitman arm, the drag link TRE also has 3/16" clearance to the track bar.

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Frame notched, Tire rubbing on fender and drag link has just enough clearance to lower radiator. Left side full stuff, differential cover has about 3/16" clearance to the track bar. In terms of a forward stretch, I netted 2.5". With the flattened pitman arm, the drag link TRE also has 3/16" clearance to the track bar.

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I think being forward like you are with the front stretch makes your uptravel job harder. I was able to almost stuff into highlines without notching the frame. Also the offset TRE you run on drag link pushes the drag farther into where the frame slopes down.

It looked like you are getting contact from track bar bolt head to your drag link. Did you consider highlining the metal cloak fenders? They look great moved up 3" IMO.

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I did consider it. I know driver side, I could gain more height easily. Passenger I'd have to consider factory knuckles.. drag like TRE has a credit card gap to the track bar bolt head.

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I did consider it. I know driver side, I could gain more height easily. Passenger I'd have to consider factory knuckles.. drag like TRE has a credit card gap to the track bar bolt head.

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It's interesting to see the effects of choices. Not right or wrong just cause and effect. I didn't push my track bar as far forward and I have a 5" pitman arm so I have clearance to run a straight TRE on the drag and can sneak my HyDro assist hoses between them.

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Interested to see your sway bar and hydro setup considering you're already packaged tight! Did you get your coilovers yet?
 
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i have stock knuckles and still had to take a chunk out of the frame.
and i pushed my TB mount up to within 1/8" of the straight pitman arm and still no way in hell a straight bar would clear my diff for full unimpeded travel.
 
It's interesting to see the effects of choices. Not right or wrong just cause and effect. I didn't push my track bar as far forward and I have a 5" pitman arm so I have clearance to run a straight TRE on the drag and can sneak my HyDro assist hoses between them.

View attachment 309824

Interested to see your sway bar and hydro setup considering you're already packaged tight! Did you get your coilovers yet?

I plan on hydro. A 6.75" ram was ordered yesterday. I have a route for the hoses but I may end up shortening the 3/4" track bar mount to sneak them between the TB & DL as you did. I have a set of 12" Fox emulsions on the shelf. This is the area where I'll need some help. I see alot of guys mounting tabs on top of the axle tube. I'd like to get it lower, behind the axle, so my shock towers aren't so high. We will see. What brake hoses do you have? I was debating on running individual lines on the upper link but are yours long enough with 12" travel?
 
I plan on hydro. A 6.75" ram was ordered yesterday. I have a route for the hoses but I may end up shortening the 3/4" track bar mount to sneak them between the TB & DL as you did. I have a set of 12" Fox emulsions on the shelf. This is the area where I'll need some help. I see alot of guys mounting tabs on top of the axle tube. I'd like to get it lower, behind the axle, so my shock towers aren't so high. We will see. What brake hoses do you have? I was debating on running individual lines on the upper link but are yours long enough with 12" travel?
Run an single line down the UCA to a tee then individual lines to each caliper. Block one port on the distribution block. Convert everything to -3AN.
 
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I should have taken more pictures as I built the axles and I should have machined the tubes/DOM. I used 3", 1/4" wall DOM tube for the sleeves. I purchased a McMastercarr tight tolerance aluminum bar as an alignment bar and machined some pucks to check both the front and rear axle. Front axle had a little bend to it but nothing a couple of carefully placed rosette welds and the chain/bottle jack technique didn't fix. As for the driver side, I pressed on the sleeve as pictured but I made the mistake of not de-burring the sleeve and it took quite a few ugga-dugga's to get it to fully seat.

I was able to press the drivers-outer tube w/ axle C in my shop press, carefully checking DOS every 1/2" to make sure it was going in straight. It maintained same degree until fully seated. The passenger side was the Bitc#. It twisted on me to end up being 1 degree off from the drivers side. A 4" relief cut in the sleeve, the axle clamped on a table and a long piece of pipe welded to the axle C gave me the leverage to get it matching the other side. After I slowly welded, the axle stayed true with the alignment bar.

Both axles, I used the chain/bottle technique when I burned in the trusses.

I thought about the 44/60 hybrid but I'm hopeful these axles will hold up to 37's. I'm just wondering if the 1310 U-joint decision was a good one or not.
From what I understand using the 1310 as the fuse in the system is the easiest trail fix and limits axle shaft failure.
 
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