2005 Toyota Highlander AWD has a front seal on the transfer case leaking. Is there an additive that can be added to the transfer case that would help?

This the one....ATP AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle ?

Yes, that's it, works pretty well on rubberized shaft style seals, but does nothing to help out gaskets or deteriorated sealants ("form a gasket" silicones).

Well crud....I am trying to find out if the seals on the 2005 highlander AWD are rubberized or gasket type and the Toyota parts dept. has no idea !! Any idea?Thanks for all you time on this!

Well the issue with many Toyota awd systems is the design of the front RH axle bearing area, it uses 2 oil seals, one to keep ATF from leaking out, a vented area, and then another seal to keep gear oil from leaking out. If it's leaking red ATF fluid around that RH drive axle, don't bother, as that's transmission fluid coming from the transaxle, and that seal will need replacing as you don't want to put additives in the ATF outside of the factory trans. oil. If it's gear oil, then it's coming from the transfercase, and the AT-205 then might help seal it.

Great Info....thanks so much. It is definitely not red ATF fluid and is actually weeping right at the front transfer case seal (just a drop or two after each run), so it sounds like the AT 205 is worth a try.