OIl in axle housing

[og]

I have noticed oil leak coming from a cracked boot on the front differential. I have dumped the oil from differential, and it looked it was normal amount although I did not take a precise measurement. When I split the axle, small amount of oil came from the half of axle housing coming from the differential. Inside, there was more oil in the small puddles as inside is not smooth as it has some reinforcement ribs. I guess there are seals on both sides of the axle, so is there any way to figure from which side is leak coming? My plan was to replace two O-rings and seal in the metal ring only, as that should fix boot leak. And boot itself, of course. But the still small oil amount in the axle housing is not really normal, I presume. Is this the dreaded "inner differential seal" problem? If so, can someone point which part would that be.

Thank you

[rmel]

Not uncommon for leakage from the Diff to a Axle.

What I recommend as part of your routine maintenance is to check and replace
the fluid in the Portals every 3,000 to 5,000 miles. Pull the top Portal plug to see if a
lot of oil pours out, if so that excess is coming from the Diff. A little is not a
serious issue. Then also top-off your Diff's at the same interval and see how
much that takes. Don't be surprised to see a few Ounces of Gear Oil per 1,000 mi.

[og]

Thank you for your reply. I was not aware that there is no seal on the portal side.

[rmel]

There is a seal they can leak


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[ChickenPinz]

Is it true that there is no breather on the diffs? If so, I'd expect it *has* to push oil out somewhere during pressure increase (from temperature) events. Perhaps the design is such that it'll push out the axle seals first before the input shaft, and then it's just a matter of periodically topping up the diffs, and draining extra from the wheel drives? In that case, oil in the axle boots would be normal.

[rmel]

My Pinz'ies have Diff breathers. A 71 and and a 73.
Can't say if all do though.

[Hugues]

My 710 has a breather on the front diff but not on the rear.

[og]

Mine doesn't. I never really touched diffs after longer drive to figure if they get warm. In any case front one should not get warm if not in 4x4?

[rmel]

It's a good idea for the Diff's and Tranie to have breathers. Easy to install.

By the way, the front Diff will also get warm. There is no means to disconnect
the short shaft when driving so it gets dragged along spinning so the rotating
gear set and shaft will generate heat. The older Rover Series had a free
wheeling Hub to turn ON/OFF that connection when in 2WD -- though I'd
rather have lockers