Replacing the Front Inner Axle Seals on a '99 XJ Dana 30 Axle. I made it at TechShop.™

Picture of Replacing the Front Inner Axle Seals on a '99 XJ Dana 30 Axle. I made it at TechShop.™
After taking my comanche wheeling in Pismo Beach I noticed a small puddle gathering around the base of both my front tires. Some checking of the brakes and brake lines revealed that the actual culprit was diff fluid leaking from the ends of the axle tubes. My inner axle seals were shot.


I made it at TechShop.™

To get more information on TechShop and TechShop locations, visit:
Remove these adsRemove these ads by Signing Up

Step 1: Remove The Wheels, Calipers and Wheel Spacers

Picture of Remove The Wheels, Calipers and Wheel Spacers
After jacking up the front end, the first step in the process was to remove the wheels and the front break calipers. Be careful, when removing the calipers, to not let them drop as they could pull loose the break lines. After removing them from the rotos, we placed them on top of the control arms. We also removed my wheel spacers which were holding on the rotors.

Step 2: Remove The Rotors

Picture of Remove The Rotors
After removing the calipers and the spacers, the rotors slide right off.

Step 3: Remove The Hubs

Picture of Remove The Hubs
The next step is to remove the three bolts holding on the hub. They are in a triangular pattern. Quick side-note - they should be torqued to 75 ft/lbs when re-attaching.

Step 4: Remove The Axle Shafts

Picture of Remove The Axle Shafts
After removing the 6 hub bolts from the axle shafts, they should both slide right out. So far, so good. And easy.

Step 5: Remove the Diff Cover

Picture of Remove the Diff Cover
Now that the axles are out it's time to take apart the diff. We removed all of the bolts holding the diff cover on. Straightforward.

Step 6: Draining the Diff

Picture of Draining the Diff
After all the bolts are removed the diff cover must be pried away from the housing. If it was installed properly prior, it should still be held on by the gasket. To do this, we used a flat-head screwdriver and a mallet to open a crack in the gasket and then pry from there. Make sure to have the oil pan ready and don't pry too hard at first to prevent the oil from splashing. After opening the initial crack, we let it drain before prying it away completely.
Great instructable! IMHO the outer seals were the most important thing for the reader to take away from this. They are infinitely easier to change than the inner seals... It's almost a "why didn't the factory do this?" thing! I imagine someone swamping with bad inner seals could just as easily get some aggregate -inside- the differential and possibly lunch the ring & pinion.
Rainh2o2 years ago
You can also press the new seals in by using a socket and a long extension or pipe. find a socket that fits the seals (cant remember what size i used) and then place it over the seals like you did with the tool you made in the picture and then drive them in gently the same way. Helps to have someone who can watch was is happening to hold the socket or work the hammer to press them in. Great Instructible! Same process on a Wrangler TJ
Husafan (author)  Rainh2o2 years ago
Thanks! From what I read on the web, a 1-7/16 socket is the size to use. We went the homemade route because we thought it'd be cheaper. Dunno if that's actually the case. :) Also, +1 to your comment about having another person. I had a couple of friends helping and it makes all the difference!