Howdy,

Hoping some of you could help me Identify and remedy the leaks I'm having on the XJ. I know the oil filter adapter is leaking. I'm waiting on that bear for another day. I'd appreciate any and all advice.

Pictures:

Front Diff/Drive Shaft:



Oil Nut:



Another Shot of Oil Pan Area:



T-case:



Oil Filter Adapter:

 

My standard reply.
　
I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.
Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.
Many mechanics, friends, people on Jeep forums who can’t see your Jeep from where they’re at, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?
A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.
First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.
Revised 02-26-2013

 

Yep. What he said. ^



Look higher. You showed a pic of the bottom of the t-case but it is probably the output shaft seal that is leaking. Follow the clean trails that are left by the fluid running down. Pic of the diff is a pinion seal. Check the valve cover gasket, a very common leak that will run to the bottom. Also make sure to use the right size wrench on that drain plug