I don't have a total answer for you. But I've just replaced the front axle seals in my 78 cj5. They are located on each side of you pumkin (Inside ends of axle tubes). Installed from the inside. I think you may even have to pull the third member to install the seals. This appears to be the only thing that could be the problem. But I was in there replacing the r & p. I didn't have a leak. I only replaced the seals after dis-assembling the axle. I didn't want to be in there again. The seals are cheap. $10 at Advanced Auto.