I have an 04 Discovery with 61k miles. I noticed a couple of months back that I had a small drip coming from somewhere near the transfer box. More specifically there is gear oil on the cross bar, bottom most bolts of the transfer box plate and also on what I believe to be the hand brake assembly.

At 60k I changed the oil in the front and rear diffs, transmission and transfer case. I thought the leak was coming from the transfer box plate so I pulled it off, cleaned it and put some new gasket material in place (Permatex Black) and refilled with 75W-90 Synthetic. The drip is still there and after reading some forums I am wondering if it is being caused by a breather tube problem. Every once in a while I can smell ATF and gear oil when I am driving.

I am also suspecting the breather tube problem because I had my windshield replaced and read that they are somewhere near the firewall. I was not happy at all with their workmanship and wonder if they may have damaged the tubes in the process, I know they had my hood removed at some point.

First of all I need to find the outlet of the breather tubes. And second, is there and easy way to see if they are plugged/damaged?

Thanks

 

The seals in my transfer case had to be rebuilt under warranty by the PO at about 40k

 

Someone correct me if I am mistaken but I believe the breather tubes are attached to the rear of the right hand (passenger side) cylinder head. They attach to the head with a double sided clip -- not very easy to get to, maybe you could find a way to hook a longer tube to the end of it and route it somewhere you could see it during operation? Just a thought...