With lots of mileage and lots of wheelin’, you might start having problems with your ball joints. I noticed it with a lot of up down travel on one particular side after a hard weekend of wheelin’, plus some non-typical pull to the right when I let off the gas. A worn or damaged ball joint is a safety hazard, but is an easy fix to replace with a bit of time and the right tools.
(This write up is not intended to be used as a definitive text and is to be used at your own risk. It’s just how I did it and it’s intended to be a helpful resource. As with any online write up, the user assumes all risk for work done. If you have additional tips or an alternative way of doing it, please let me know and I’ll update the write up periodically.)
Changing the ball joints was a lot easier than I expected, but you do need a ball joint press to do it effectively. I borrowed one from “sweathog”, but AutoZone has a loaner tool and Harbor Freight sells the kit I used for around $40. The AutoZone loaner isn’t ideal for 4x4’s, but it will get the job done. Since the front end of the XJ’s, TJ’s, and ZJ’s are all almost identical, the procedure works for all of them. Today’s example is on my 93 XJ.
(It took me less than 2 hours start to finish for me first time doing it and taking pictures, etc, including clean up. Most of the time was spent figuring out the blasted ball joint tool and adapters. Give yourself plenty of time and don’t rush it, but this is not a time consuming project with the right tools.)
As always, make sure you have all the necessary tools prior to starting the job. Tools required for this repair are:
• Floor jack
• Jack stands
• Ball joint tool (basically a 6” C clamp with adaptors for the process)
• 3/8” and 1/2" sockets and a 13mm wrench
• Ratchet and breaker bar
• Needle nose pliers
• Ball joint separator (pickle fork)
• Really big, scary hammer
• Torque wrench
• Grease gun
• New ball joints ($60 for upper and lowers at AutoZone)
• A radio playing old country music
• Old rags for wiping your hands since this may get dirty
• Beverage of choice (coffee in my case)
Step 1: Jack up the Jeep and remove the tire. I just did the left front, so I made sure I was on level ground (for this adventure I choose the garage so it was level AND shaded) and blocked the back wheels prior to jacking it up and putting the front axle on a jack stand and remove the tire.
Step 2: Remove the brake caliper and pads. It is quick and easy with just two bolts to be undone with the 1/2” socket on the back of the assembly. Be careful with the break line. I had a second jack stand handy so I just rested the entire caliper and pad assembly on the jack stand so as not to put too much tension on the break line.
Step 3: Remove the hub bearing and axle shaft. You can certainly remove the rotor as part of the brake caliper and pad assembly, but I just kept my rotor with the hub and pulled the entire axle. There are three retaining bolts (13mm 12 point heads) that need to be removed. The picture below shows 2 of the 3 bolts, the 3rd is easy to find on the front side of the knuckle. I’ve had to replace my front axle within the last year, so the hub assembly and axle came out pretty smooth, but if it’s been awhile, you may need to use some PB Blaster and a little “coaxing” to get the hub out of the knuckle. Once removed, it’s good idea to inspect your axle shaft for any wear or twisting.
Step 4: Remove the retaining nuts on the ball joints. At the bottom of each ball joint is a retaining nut and cotter pin. Start by removing the cotter pins. You can toss these out as most new ball joints come with new nuts and pins, but please check and make sure before you mangle these, toss ‘em, and then get frustrated you don’t have a new cotter pin.
Step 5: Use the ball joint separator (pickle fork) and the really big, scary hammer to separate the knuckle. Seriously, put the pickle fork below the upper ball joint and above the knuckle and just smack it. Typically, when you separate the upper ball joint, the lower will separate.
If your ball joint was as shot as mine, it may actually come apart on you end up with ball joint parts. In other cases, the shot to the upper may not separate the bottom at the same time so you may need to use the pickle fork on the lower joint as well to drop the knuckle. The picture below shows the knuckle separated from the ball joints.
You do NOT have to disconnect the knuckle from the tie rod, so I just rested mine on another jack stand to secure it and to keep it from moving around on me.
Step 6: Remove the old ball joints. This is where the ball joint press comes in handy. You will use it to remove the old joints and to press in the new joints. (The problem with the loaner tool from AutoZone is that it is designed for applications where everything is flush. On 4x4’s the mounts for the joints are on a slight angle with respect to the joints themselves. In other words, you are trying to get leverage off an angled surface to press the joints in and out straight, making it more difficult than it should be, so it’s worth it to get the right ball joint press for 4x4’s.)
The Upper Joint needs to be pressed UP in order to remove it and the Lower Joint needs to be pressed DOWN. Use the instructions that come with the ball joint press for what adapters to use, or (if you borrowed a press like me that didn’t have instructions) waste a lot of time figuring out what goes where and then eventually get it right. Also, as a safety reminder, you are applying a LOT of force. Be safe and aware of your surroundings and be out of the way in case deflection or warping of the press and something breaks.
***REALLY HELPFUL HINT*** Remove the upper ball joint first so you can run the rod of the ball joint press through the opening of the upper joint to get the proper angle on the lower joint. If you have a lift and can get under it, I guess it doesn’t matter, but when working with limited space in the garage, it makes a big difference.
Step 7: Press in the new joints. Now this is going to sound strange, but it makes sense and I did it. (This tip is courtesy of Sc00by.) He suggested putting the ball joints in the freezer for a couple of days prior to installation to help contract the metal. When pressing them in, I took one out of the freezer at a time, applied a liberal amount of WD-40 to the opening, and pressed the cold ball joint in. You are pressing the joint into a very tight space (and you want it to be super snug for safety and performance reasons) but it can be a booger to press in. It seemed to make a difference, but I don’t have a non-frozen frame of reference. Anyway, here’s a pic.
The Upper Joint needs to be pressed DOWN in order to install it and the Lower Joint needs to be pressed UP. I would suggest beginning with the lower for the same reason as you removed the top first… it allows you to run the rod of the ball joint press through the upper opening and maximize your space. I took a short cut and used my impact gun to apply force to the lower (make sure it’s straight when pressing it in), but I had to use a breaker bar and socket set for the upper due to space issues.
Be sure you are pressing the joint all the way flush. You want this to be a firm fit without any play or danger of coming out or loose. At this point, you will want to install the zerk fittings if they aren’t already and grease the joint prior to installing the knuckle. It’s just a lot easier without everything reconnected.
Step 8: Reinstall the knuckle and torque the nuts to spec. Now you can re-attach the knuckle, torque the nuts to spec and reinstall the new cotter pin.
Step 9: Reinstall the hub bearing and axle shaft. Do the reverse of Step 3 above. Make sure you clean the splines on the axle shaft and apply a film of grease before reinstalling. Make sure you are careful when inserting so that you don’t damage the inner seal in the dif.
Step 10: Reinstall the caliber and pads. Do the reverse of Step 2 above, torque to spec, yada yada yada.
Step 11: Put the tire back on and drop the rig. You are done, dirty and sufficiently proud of yourself for knocking out this repair with little blood spilt and very little cursing. Always a success. Make sure you take if for a test drive (carefully until you are sure you tightened everything!) and you should be done.
Overall, it was $60 and 2 hours well spent on safety, performance, and a repair I could do on a Saturday morning in my own garage. (Again, this write up is intended for informational purposes, but I am neither a mechanic nor an expert, just a weekend wheeler learning to wrench at home. User assumes all risk for this repair.)