What Diff do I have?

[Bumpy]

Hey all.

Recently I purchased a 97 Galant VR4 with the manual gearbox. The issue the seller had was a knock coming from the rear end. I was happy to buy the car as it was very cheap. After getting the car up on stands it showed that the rear diff looks to of been changed and the result was the rear subframe bushes had been ripped out from the subframe due to there being a 12mm gap from the bushes to the back of the diff and a previous owner cranking the rear mounting bolts up tight thus tearing the bushings from the subframe. I am very confused about this as 2 people have told me the diff should bolt straight in but there is no way the diff could go any further back towards the fixed bushings. Just wondering if anyone else has had this issue in the past. What is the diff in my car? Evo ??? or something else. The other issue im having is that the AYC lights keep coming on every now and then intermittently even when just driving of not even. That actually is of more concern. Any help is much appreciated.

[Davezj]

It sounds like it has had an evo 8 sayc diff fitted they require 10mm spacers between diff and subframe to allow the diff to be aligned correctly.

[Nick Mann]

Not necessarily an 8, could be a 7 or 9 too but evo diffs bolt in with a gap at those rear mountings. The lugs are 10mm shorter than ours.

[Davezj]

I thought the 5-7 ayc were exactly the same as vr4 apart from the prop shaft flange., and The 8-9 sayc needed the 10mm spacers and the prop shaft flange.
But I don't know for sure, I am probably wrong.
However back to the point, if the bushes have been ripped out of the subframe then it is the perfect opportunity to replace them poly bushes. And get some spacers or use some washers to pack it out.

[swinks]

Dave, difference is not due to ayc vs. s-ayc, but Evo chassis, floorpan and suspension, hence Evo 4-6 vs. Evo 7-9. That's why difference in diff casing.

[Davezj]

Ok, if you know for definite and you are sure all the 7-9 evo diffs need the spacers. That is great news at least the guy knows it can be a ayc diff or an sayc diff.
I was not sure this was the case which is why I posses the question.
It seems odd that mitsi would have a working and In production diff then go and create another diff case but slightly different . You would have thought the bracket for the diff would have been changed and not the diff.