How to replace ball joints/axle u-joints

[dave92cherokee]

This write-up is based on my 1992 Jeep Cherokee Sport 4.0 4wd other years might be different but should still be fairly close as from what I’ve seen Jeep has stuck with the same configuration for the most part. For the ball joints you want to be careful when getting them as autozone and advanced auto parts didn’t have their list made right when I got mine, when you get the ball joints the upper ball joint is listed correctly but when you get the lower ball joint make sure that the ball joint does not have the grease fitting in the top of it as it will not work due to the u-joints in the axle shaft sitting right above them you need the lower ball joints that do not have the grease fitting or the hole for one it has to have the sealed case. While you are replacing the ball joints if you have high mileage on your jeep then this would also be the perfect time to replace the u-joints in the axle shaft since you will have it completely removed from the vehicle.

Tools needed: standard and metric socket set, wrench set (and 13mm star box end wrench), allen wrench set, ball joint separator, weighted mallet, ball joint replacement kit (available on loan a tool from auto zone), 36mm socket (or 1 7/16) can be hard to find but I found mine at a tractor supply store, breaker bar to fit socket for removing axle hub nut, torque wrench, grease (loose and gun), cleaners and lubricants to clean area before reinstallation of ball joints and axle shaft, assortment of cotter pins.

Removal

1. Jack up the vehicle and put jack stands under the frame not the axle so the axle has enough clearance to work and remove the wheels.
2. Remove the brake calipers and hang them out of the way with a wire or metal coat hanger then remove the brake rotor and set it aside.
3. Disconnect the tie rod from the steering knuckle and use a piece of string to hold it back out of the way.
4. Remove the cotter pin and lock nut then using the 36mm or 1 7/16 socket remove the axle nut.
5. Remove the 3 hub to knuckle retaining bolts using the 13mm start wrench then remove the hub and brake splash shield.
6. Slide the axle shaft out of the front axle at this point I would recommend inspecting the axle u-joints and/or replacing them at your discretion as it proves to be quite a job to get the axle shaft out.
7. Remove the cotter pins and ball joint nuts then using the ball joint separator and mallet alternate from top to bottom driving the knuckle down off the ball joints.
8. Use the ball joint replacement kit to press the old ball joints out, at this point you are done with the removal and before you start the installation I recommend using some brake parts cleaner and wire brushes to clean the area up before reinstalling.

Reinstallation

When reinstalling the ball joints before pressing them in I recommend using a little bit of grease inside the hole and around the outside of the ball joint to help when pressing it back in. Installation is the reverse of the removal like most things but make sure to use new cotter pins for the axle lock nut.

If you have all the parts you need and tools ahead of time before undergoing the job it should only take a couple of hours per side. Make sure you only do one side at a time so when reinserting the axle shaft it lines up in the differential correctly. Just remember when getting the ball joints make sure the lower ball joints are the completely sealed design the ones with the grease fittings come with the little bolt that you can use to plug the hole but even that bolt head is to tall for the space between the ball joint and the axle shaft u-joint. After everything is put back together grease up the entire front end and check the ball joints to ensure any previous play is now gone.

Torque specifications:

Knuckle to ball joint nuts 100 ft. lbs.
Hub to knuckle bolts 75 ft. lbs.
Axle nut 175 ft. lbs.
Brake calipers 7-15 ft. lbs.
Tie rod ends 35 ft. lbs.


If any of you can think of something I might have forgot to mention please don't hesitate to throw it in.

[AlohaBra]

I am going to close this thread as it is just intended as informational and not a discussion on things like different brands of u-joints and such.