E30 Zone

i know all the diff's have a tag with some numbers so you can identify what they are but how do i tell a small case from a medium case diff ?

basically im after a med case 4.10 diff so how do i know thats exactly what im getting if/when im offered one ???


cheers

i could've sworn i saw a thread will all the diff codes etc but for the life of me i cant find it.

the first numbers on the tag tell the ratio so 3.91 is a 3.91 diff. An S in before the ratio means LSD. some tags however will have 4311 this means 43 divided by 11 so 3.91. if you cannotread the tag spray it with WD40 and rub it with a brillo pad

as for the sizes a the larger diff for 325 has eight bolts holding rear cover on, the smaller (320/318) has 6 bolts

is there only 2 size diff casings then ??? i thought there was small, med and large ???