Hi all.

I have a jdm Evo viii with rear diff issues. Looking at options for replacing. As I don't want to give up my AYC I'm wondering if anyone has attempted puting an Evo x AYC diff in a viii. I've see lots of infor going the other way people putting Evo ix rs diffs into Evo x's

 

I'd ask the LancerRegister forum this question since they had the Japanese-spec cars. EvoM is largely US-based, and the USDM Evos didn't get AYC.

 

Cheers will give it a go

 

A friend is putting one in a 6. IIRC there was some difference in one of the output CVjoints but nothing major.. .will ask him to chime in..
AS far as functionality is concerned.. it is the same..

 

The left CV joint has to be combined X stub and 8 axle half. The issue is that the original ***** do not fit and you need to find tool-steel pins to make work.
I had somebody do this for me, who took 6 months, and is unlikely to do it again.

If I were you, I would buy X left shaft complete and take off the left stub and figure out how to assemble the X stub instead of 8 onto original 8 CV/Shaft.

Anything can be done, but time is hard to find, to dedicate to the project.

 

Awesome thank you

 

Awesome not as difficult as I way expecting. As far as the ayc pump is concerned nothing changes. Just drive the x diff with pump from the viii

 

Nothing changes for the Pump. The only advantage of the X AYC over 8 AYC, is that it's newer. I am not aware of any technical update which would make it better. Both should be essentially same Super AYC

 

Awesome. Main reason for changing to the x was easier to source and better pricing than an viii. Other than that was hoping maybe the later model might have slight better oil flow to the pinion bearing.

 

truth be told, pinion bearing is really not any problem to change... bearings are standard off the shelf items and you do not even have to take the diff off the car..

evo 9 and 8 diffs are identical and interchangable..

 

Hi Alpinaturbo,

sorry to revive old thread but was wondering about this swap. According to my research the EVO 4 to 9 have a 3,307 rear diff ratio but the X has a 3,538. From what I know for 4wd vehicles it would mean the rear wheels would spin slower around 6,6% than the fronts. Some people say that this wouldn't matter as the center diff would account for this discrepancy and allow this mismatch. I worked for BMW technical service and just a 1% tire size difference (using older and newer tires) could cause issues with the diffs.
I don't know if you could just swap the differential gear set from the evo v to the evo X AYC. Is this possible? Since most people say the AYC is almost identical except for the left output flange I would think internally they would be very similar. Also from pictures the inner diff seems to be very similar in dimensions. The part about the machining doesn't scare me since I have a machine shop and could do that work but I'm concerned about the different diff ratios.

Thanks for the info.