danutt 4 Report post Posted November 1, 2013 i got a 3.64 diff thinking what i had in the car was taller want shorter gearing so in need of something shorter ive check real oem and shortest the e39 came with was 4.10 in thailand built 528's so what i was thinking and im hoping someone here has the know how as well as the can do attitude 3.91 diffs are medium case from e28 could the internals be swapped?what about e34 diffs etc?? Quote Share this post Link to post Share on other sites