Ok, so I disassembled my clutch type S4 diff and placed a 0.6mm shim on the outside of the conical spring. Once assembled I achieved a preload of a 90 lb-ft force. The issue I was having is that the thrust washer on the side of the shim was a bit loose in its place. I then cut another 0.6mm shim for the thrust washer for the same side. When I assembled the diff. whit the shims in place, now the thrust washer on the other side is loose in its place.

My question is, as the diff heats up the copper thrust washers will expand a bit, does anybody know the required minimum clearance between the thrust washer and the inside face of the diff housing?


Second question is, just how hot does the diff typically get on a nice track day?

Here are some of the pics of the work I did.