WJ Control Arms on a XJ (Write-Up)

Old 08-31-2010, 09:45 PM
Seasoned Member
Thread Starter
eggdashure's Avatar
Join Date: Aug 2010
Location: Grand Junction, CO
Posts: 330
Year: 1999
Model: Cherokee
Engine: 4.0L I-6
Default WJ Control Arms on a XJ (Write-Up)

Ok, go easy on me, this is my first write-up!

First of all, let's talk about why I did this swap. The WJ Control Arms are MUCH beefier than XJ CA's. The WJ Arms also have the NVH (Noise, Vibration, Harshness) bushings which really does make a difference in ride quality. And lastly, the S curve in the lower arms. The S curve makes it possible to run larger tires and not rub on the control arms as evidensed in the following pic.

So, step 1: Procure a set of WJ Control Arms...I scored all four of mine on eBay for $40.99 (including shipping) I saw people selling just the LCA's for $65. A Junk Yard visit may yield results too.
Step 2: I began by soaking any and all control arms bolts with penetrating oil. Might want to do this and let it sit for a while (2-3 days?). I then "broke" the bolts on my drivers side tire and lifted this side of the Jeep carefully placing jack stands under the axle and frame, then remove the tire and place it out of the way. Now I have a clear view of my task.
Step 3: I began by removing the bolts on the lower control arms. NOTE: Breaker bar makes this manageable! Once the nuts are off just use a hammer to pound the bolts out, I had to use a crow bar to pull them out the rest of the way. Be careful because one CA's fell right out and almost clocked me! (Yes, I am safety incarnate! ) Now you can see how pitiful the old arms are in comparison to the new ones! The WJ arms look a lot longer, but are the same measurement hole to hole.
Step 4: The WJ arms are approximately 12.5mm wider at the uni-body end. I tried to squeeze these into the bucket but couldn't make them fit, so I resorted to machining down the excess. (Just a side note, when the guy pulled the arms off the above axle the bushing housing was mangled slightly. I tried to correct this, but ended up machining the ends down too far. I had to squeeze a couple washers in the bucket to keep everything from rubbing.) Make sure to grease up the bolt holes in the arms to keep them squeaking. I found it easier to start installing at the axle end and finish at the uni-body end, but that's just me. At the axle end, I just widened the mount with a BFH! And used my jack to push it in place.
Step 5: Repeat on passenger side! For some reason the drivers side bolted right up just fine. Passenger side took some creative thinking! I just used my standard issue Jeep Jack to fine tune the back and forth position of the axle until things lined up properly.

If you only plan on doing the Lower Control Arms, great your done!
If your foolish like me and want the Uppers installed too, continue on!

The upper arms present more of a challenge because they aren't quite a direct bolt in. If you are running a stock rig, you could probably bolt them up and go. If your running a 3 inch lift like me...well just make sure you have an angle grinder and a fair amount of patience. If you look at the pic below, you'll see that the WJ arms arch downwards and the XJ arms arch upwards. What happens is the WJ arms can contact the bottom of the bucket and limit axle droop. The red circle is a clip on the arm that holds the axle breather tube on the drivers side.
Step 1: You should already have the tire off and your Heep on jack stands, with the bolts already oiled. I began on the drivers side at the axle mount, this requires a long 15mm socket (Harbor Freight here I come!). I'm not sure what year Jeep did this, but on my 99 I have the little arm that is SUPPOSED to catch on the control arm and provide resistance to remove the nut. Notice in the pic above the shiny circle around the old arms axle end mount. Here's how I eventually got this stupid bolt out, I found a piece of square tubing and pounded it on the little strip that is SUPPOSED to catch, and used the axle as a pivot point.
Step 2: The uni-body end worked just fine, but it's like playing operation when trying to remove the bolt from in it's hiding place. Just take your time and work it out slowly. If you drop it, a strong magnetic wand is your friend!
Step 3: On the frame itself is a small piece of metal that protrudes out this needs to be cut back an inch or so to allow droop of the arm. Then you will need to grind down the uni-body bucket roughly a quarter of an inch...depending on your lift you may need to adjust this accordingly. Time will tell if this weakened the bucket or not. I highly doubt it given the strength of the metal. Special thanks to Comanche Club for this adaptation!
Step 4: For the upper arms I found it easier to start at the uni-body end and finish at the axle. Why, I dunno! Only worked one way for me. Again the passenger side wanted to fight me, I had to use a come along attached to a hole in the frame near the center cross member and at UCA tower to get this SOB to line up. Sorry, no pic of the come along, I was running low on patience and time.

All done!!!

Verdict: I was quite shocked when I took the Jeep to work the next day, a much more responsive and smoother ride. I had been struggling with some DW and bumpsteer and it's no wonder given the shape my bushings were in.

It's nice to be able to get full lock steering without using washers at the steering stops. No awful rubber on metal grinding noise when I'm trying to park. The improvement in ride quality was both shocking and welcome. A very potent mod indeed!
eggdashure is offline  
Related Topics
Thread Starter
Last Post
Jeep Builds
02-16-2019 02:53 AM
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
11-21-2017 12:19 AM
Vendor Showcase
07-13-2016 12:11 PM
Modified XJ Cherokee Tech
09-29-2015 11:15 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Thread Tools
Search this Thread
Quick Reply: WJ Control Arms on a XJ (Write-Up)

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.