Hello

I'm having some issues with differentials, but I can't find any solid information for the S4 diff's

I have an 1986 S4 N/A with an open diff which i want to get rid off. So off course welding is an option, but since this is my daily I'm looking into other sollutions first. Welding is my last option.

So this is my option:
Triple-R: FC3S Buildup - Chapter 2: Part 17
However, this guy uses an S5 LSD housing? I know the S4 and S5 housings are different, so my question is, will this work with my S4 Open diff housing?
the "S4 half shaft stub axles " are also unclear for me, I know there are some different versions, but how do I know which ones I have and if I have other axles, will it work with this conversion?

Another question is, are any other diff internals interchangeable with the S4 diff. Say I weld my diff and I don't like it, can i for example use the internals of a miata to swap it back to original? Because where I am, RX7 parts are rare and expensive..

Thanks in advance!

 

Be easiest to find a s4 diff from a GXL, it will bolt right in and than no need to source half shafts or anything

 

The problem is, in europe the gxl,gtu,... system does not exist. Its just an S4... how to spot the gxl diff?
And rx7 parts are rare and expensive. So im hoping something of another model would work as it would be easier to find/afford

 

I've just found something about the kia sportage diff being a direct bolt in for the FC rear end?
So the complete pumpkin is a direct swap?? or am i reading this wrong?