dolson222

iTrader: (9)

To clear this up a bit further because it seems like info has been unnecessarily confusing. The ACD and AYC beth require hydrulic control to activate (hence two fluids-gear oil and a control system fluid).
so...
Transmission/ Gearbox:
- Either the DiaQueen rocommended or AMSOIL MTG 75w-90 or REDLINE MTL 70w-80 . MT-90, will work (quoted from OP) NOTE: EVO X MR fluid is different!!!

ACD:
- Control System Fluid: Some form/brand of ATF SP III
- Differential Fluid: DiaQueen LSD or AMSOIL SEVERE GEAR 75w-90 or REDLINE 75w-90

AYC rear diff: (not i do not have AYC but from what has been said between international
evos and USDM evo x guys this is what I have determined)
- Control System Fluid: Some form/brand of ATF SP III
- Differential Fluid: DiaQueen LSD
(NOTE: AMSoil DOES NOT recommend a fluid other than stock
DiaQueen LSD for the rear diff but many use it in the rear as well since
they say its good for the ACD diff as a replacement for the OEM fluid.
I am also about to make this swap to AMSoil for my non-ayc rear diff
too)

Many places say that you should only use DiaQueen LSD in both center and rear diffs but if you want to run all synthetic fluids then DiaQueen LSD is out of the running.