99 Suburban Transfer Case Fluid Leak

I have a 99 Suburban and the fluid from the transfer case tends to leak out over a period of time. I have not been able to specifically identify the leak location as everything tends to be oily around this area and was wondering if anyone can provide any insight of similiar problems. I was wondering if transfer case seal is probably the problem. And if so if there are any hints/tips for this replacement. I'm not that experience in automotive overhaul actions but I did complete the intake gasket replacements as listed by Suburban 97 on here (not a novice but not a pro either). Any help would be greatly appreciated. Thanks, by the way I just found this forum and have to admit it is GREAT!!!!

There is a gasket between the transfer case and the housing on the transmission.I believe it uses the special blue fluid that is a dealer only for the transfer case and not ATF.

There is a gasket between the transfer case and the housing on the transmission.I believe it uses the special blue fluid that is a dealer only for the transfer case and not ATF.

Humm first I heard of this blue fluid, I have been putting in the regular stuff per my owner's manual specs. Do you happen to know where I can find a service bulletin on this or anything like that.
Also wondering if anyone has experienced this fluid lost issue and what was their problem.
Thanks for the reply, greatly appreciated

GM starting putting it in their transfer cases about 1999 and it is called Auto Trac II about $6.00 a quart from the dealer only.It even works better in the early Oldsmobile Bravada transfer cases than the ATF.

2 main leak areas besides seals is the rubber plug on top which has been updated (cheaper from the chrysler dealer) and the pump wears a hole on the passenger side of the rear T-case half on one of the ribs about 1/4 way up.

2 main leak areas besides seals is the rubber plug on top which has been updated (cheaper from the chrysler dealer) and the pump wears a hole on the passenger side of the rear T-case half on one of the ribs about 1/4 way up.
one new transfer case please! tracII only

Wow!!! New transfer case, now I was not expecting that. Guess I will have to get under there and see exactly where the fluid is leaking out. At least I know of a couple high probably locations. Unfortuately I just had disk removal surgery in my neck so it will be a few months before I undertake this. Thanks for all the replies and if anyone else has experienced this problem please feel free to drop a response even if it confirms one of the previous possibilities.

a leak is a leak, but if too dirty/oily to find, then clean the area(brake cleaner works ok), fill to correct level with fluid, and recheck in a week or so. hope it is the cheaper route of a seal and not the casing. best of luck!