Disclaimer: I searched here and on Google and still couldn't get a complete answer to my question: "What are the differences in differentials that are used on the Evo 8 & 9?"

From various sources (here and elsewhere), this is what I've come up with:

2003 - 2004 Evo 8 (all models):
Front: Open Diff (2004 Evo RS got a front helical LSD)
Center: Viscous LSD
Rear: Mechanical Clutch-type LSD

2005 Evo 8:
Front: Helical LSD
Center: ACD (electronic LSD)
Rear: Mechanical Clutch-type LSD

2006 Evo 9 (all models):
Front: Helical LSD
Center: ACD (electronic LSD)
Rear: Hydraulic LSD (not quite sure what this is. Torsen?)

No Evo 8/9 had the AYC.

Anyway, is the above correct? If not, please let me know and give me a source for your info. Thanks!

 

Rear diff in the VIII is the same as the IX per Shep.

I just got done doing the fix on the plates and can confirm rear diffs are the same.

 

looks correct... I think something is on wikipedia about that

google: Mitsubishi Evolution

and click the wikipedia link

 

Negative. I have one with AYC. European spec.

 

We're talking USDM Evos.

 

I believe. Just tried to be informative.