After reading a post about front axles leaking I crawled under my 08 4x2 and sure enough, with 22,000miles, the rear axle is leaking. It's leaking on the driver side of the differential and both sides of where the axle meats the wheels-sorry not a mechanic-not sure what part that is. Take a look.

 

Thats the exact place mine is leaking. It's in the shop right now for the work and should have it back this afternoon and I'll report the details. They are also looking at a vibration at 100KM+ in the rear end that might be related, but I suspect that will come back "no fault found".

Although mine seemed to be leaking a little more with a small puddle in the driveway, not sure if seepage is normal at all.

 

Truck is back and they replaced a rear axle stub shaft seal. Guy says its pretty common on these rigs. They weren't able to find the vibration which is fine for now, might just be in my head now that I'm thinking of leaking axle's. They said bring it back if it gets any worse.

 

This is what mine looked like before the fix:


2008 Expedition Max 4x4 Limited

 

Now that is bad! Were your outer seal near the rotors leaking too?

 

No just that one for now. I'm glad I read on another thread on this or I would have never gone under to have a look. I'm going to make sure I get under there at least once a month just to keep an eye on things.

BTW this was the rear diff and the axle towards the driverside tire.