I have a 99 Disco II that has developed a leak. Found red fluid on the driveway where the disco was parked. My first thought was to check the transmission fluid but after crawling underneath, it has red fluid drops on the rear bottom of the transfer case, right around what looks like an inspection cover.


So I drained the transfer case, which had gear oil not red fluid, pulled the inspection cover on the transfer case and replaced the gasket and refilled. I checked the transmission fluid and it was low, so I topped it off to the fill plug.


It is still leaking but I cant figure out why, how or where the transmission fluid (red fluid) would be coming out to collect around the back of the transfer case. Any help would be greatly appreciated.

 

Possible causes of leak:
-Oil cooler lines loose

-The rear extension housing seal of the transmission

-Sump Gasket

-A leak from anywhere up front on the transmission might be blowing back on the T-Case while driving making it look like it's coming from there.

 

I think I found it. Pretty sure you were right, it is the rear extension seal. After an exhausting inspection of everything underneath, I found a bead of red fluid running between the 2 housings. Looks like I'm dropping the transfer case to replace the seal.


Any helpful tips on replacing the seal? certain size socket to use as a press for the seal? Thanks for the help.

 

I have not yet had to drop my t-case so I don't have much advice to give you. I am planning on removing it soon to re-seal everything, install new output flange, and inspect all the bearings but I have been putting it off.

While you have the T-Case out you might as well reseal all of the covers with new RTV. They tend to start leaking and it will never be easier to seal it.

 

Does anyone have any helpful hints on getting the old seal out. I've pulled axle seals before but it was when there wasn't a shaft in the way. Since the transmission output shaft is still there I can get a hold of it. Should I just puncture it with a screwdriver and then pull from there?

Also, what a PITA it is to drop the transfer case just for one seal....lots of knuckle busting and wanting a bigger hammer.