[E30ROB]

UPDATE:


I had very good luck! have now logged over 900 miles on the diff and had the fluid flushed at 500.

the only additional part for this swap was the 135i rear driveshaft half, which slid right into the 128i front half!

The diff bolted right into the subframe as expected, as well as the axles bolted directly to the diff with no issues and I was able to "compress" them in a few inches.

As far as the driveshaft goes, I ordered a 135i "automatic" driveshaft, separated the halves, and slid the 135i rear half onto the 128i front half with new a CSB and new hardware as well as a new rear driveshaft lock nut.

the driveshaft lined up perfectly, simply R&R and BOOM, a 3.46 Helical Team MFactory 215mm fit right at home.

Very happy i did not listen those who said to stay small case and use the 3.73 as the 3.46 is PLENTY!

CHEERS!