I have a s4 T2. My diff was replaced by the previous owner. I no longer have contact with him. I am trying to find out whether or not I have a clutch type from an s4 or a viscous type from an s5. Is there any way to tell, without removing the stub shafts if it is a s4 or s5 diff? I have searched the net and I cannot find an answer to this.

 

clutch type has the LSD oil tag on the fill plug, S5 does not.

of course the tag could be missing though..

 

Part number? Anything?

 

there is no part number stamp and no easily discernable difference seen on the outside of either unit.

you could pop out a stub shaft and compare them to the ones listed on the mazdatrix site:


the stub shafts are noticably different between the 2 once removed.