[AC TC]

It seems to be just plain old ATF of better quality...redline c+ seems to be popular and if that works so should atf+4 do it also.
- i would actually either use atf+4/ redline c+ or a good utto oil.( Utto= universial tractor transmission fluid. made for gears, clutches, hydraulics and wet brakes. Dirt cheap on large jugs..)
In a cold climate i would choose atf.

 

[AC TC]

I've been reading with the clutches in the autoAWD that regular ATF+4 may not be good enough?

If +4 wont hold up theres nothing much more to do, its a very high quality oil designed for the high shear loads of the A-604.