Dana 30 leak

An axle seal, probably. What Jeep is it, it makes a difference...YJ's and some XJ's had a vacuum disconnect on the pass side that can leak as well.

• * * Matt Macchiarolo
  formatting link
  formatting link
  formatting link

If you have a YJ or XJ with the disconnect axle it's very likely the leak is caused by the outer disconnect seal inside the axle tube. I read over the tech article Bill posted and there's one thing the guy who left out, it's a BIG omission.

After you reinstall the shift motor & cover you MUST refill the shift assys oil supply. It is not supplied oil by the differential fill, the carrier is sealed at the bearings. The shift motor, collar, etc. has it's own oil supply and there are also seals on either side of the shift motor assy to keep it in place. Jeep has a set of special tools for replacing the two seals, but you can easily make a substitute out of threaded rod and stacked washers that fit just inside the housing..

If you don't add oil to the shift assy (it's just a couple of ounces, added through the indicator light hole) you'll quickly lose the needle bearings, the shift assy, etc. The FSM spells this out explicitly but most people miss it and it causes a bunch of problems later.