Double Shear WJ Knuckle Build
 

I've been at this project for over a month now, but I'm finally in the home stretch. Passenger's side knuckle is done. I still have to double shear the driver's knuckle, drill the bolts for cotter pins and then build the track bar.

For anyone concerned about welding on WJ knuckles, they are are cast steel. The material used to build the "double shear" is 1/4" plate and the welding was done using my millermatic 185 (240 Volt machine) with regular mild steel wire.

The setup consists of:
- Factory WJ knuckles (off an 2001 I think) with 1/4" spacer welded to knuckle (alignment of hub)
- Factory WJ Akebono calipers (1/4" washer under mounting ear for alignment with rotor)
- Factory Early XJ (pulled from my old 1991 XJ) hubs (machined diameter of hub to fit inside rotor)
- Factory 2001 XJ axles, modified to take full ring C-clips with 760 U-joins
- Ford Explorer Sport Track (5 x 4.5" bolt pattern) Rotors
- Moog ball joint
- 7/8" rod ends bushed to 3/4" bolts
- 1.25" DOM tubing for steering and track bar shafts

Here's the passenger's knuckle (ignore the run in the paint, I had to spray it heavy to get the inside coated).

Are you sure you have WJ axle shafts? I thought those used Rzeppa style CV joints instead of universals, also does your steering clear everything without bends or offset joints, and what size wheels are you running? Sorry for all the questions, looks like good work.

- Opps, I goofed on my list of parts. I'm using factory '01 XJ axle shafts (typed the wrong thing). Good catch.
- Steering clears everything just fine. I had to remove the factory trackbar mount from the axle and trim the front of the spring purchase to clear the toe rod, but it all clears the diff with room to spare.
- I'm running factory takeoff 32" tires/17" rims from a Wrangler Rubicon (using adapters to convert the 5x5 wheels to XJ 5x4.5 pattern). Lots of room. I'm going to swap out the rims for steel 5x4.5 beadlocks one of these days.

Feel free to ask.

That's great thanks for the quick reply, I've been slowly acquiring parts and knowledge for this swap for a while now. Do you plan on using 15" wheels when you switch?
Another question, looks like you have some aftermarket spring perches on the axle, why did you do that?

Looks nice. I did that swap but I used tie rod ends my track bar is longer. Do you have any bump steer? Your track bar is much shorter than your drag link

Nope, I'm sticking with 17" wheels. I like being able to stuff big breaks under my vehicles and being able to use takeoff Wrangler tires makes tires cheap (I paid $250 for all 5 tires/rims, brand new).

The spring perches are "factory" but I shifted the spring back about 3/4" in order to give even more room (turned out I really didn't need it). What you are seeing is the aluminum spacer I made for the spring to sit on. It's just there as I was tossing the idea around of using a 2.5" coilover spring. I've ditched that plan and just going to convert the front to a full coilover shock/spring combo (personal preference).

Zero bump steer. I drive it daily on the I-17 at 80MPH and it's smooth as can be. The drag link is 34.5" and the track bar is 30". I calculated it all out beforehand (I was shooting for 1:1 but couldn't) and the difference in arc length change on the street is minimal. For example, at 4" of drop the difference in arc length is 0.015" (less than 1/2 of 1/32" difference). There's more "mush" (toe change) in the tires than that. Alignment is about 5.5 degrees positive caster and 1/16" toe in (set using a tape measure in the garage). Keep in mind, I also don't have any damper of any kind on it.

When I convert the front to coilovers, I'll redo the axle side mount and extend the track bar to 34.5" so it is 1:1. For now, this works fine.