98 xj, driveshaft been out for about year decided to rebuild it and put it back in. I put it back in drives fine no vibration but I noticed a day later had some weepage coming from the center of the pan and from the cooler lines that dropping on the exhaust!!! Coincidence?? I don’t know I pulled the shaft out cleaned everything up gonna see if it leaks again!

 

Coincidence.

 

If it's dropping onto the exhaust, it could be the front transmission seal. If that seal leaks, it will drop out of the input shaft and through the gap in the flywheel cover and drip right ont the exhaust and give you lot's of white smoke. If it is that seal, it will leak once the trans fluid starts heating up, it will drip from the middle of the cover plate and flow towards the back of the jeep. Only way to replace it is to drop the trans or pull the engine.
I had them go on both of my XJs. If it's the seal, don't bother with any of the seal conditioner products. That seal gets hard and brittle and has to be replaced to fix it. Maybe you're lucky and it's something else.

 

I had the trans rebuilt about a year half ago so hopefully it’s not the front seal, just got done with a water pump this evening it’s started pouring in the driveway!!! Got the underneath all cleaned up gonna check tomorrow after I get some coolant in it!!!

 

The leak from cooler lines maybe spraying fluid on bell house or pan thus making it appear there is also a leak there.