Comma LS80W-90 limited slip gear oil. GL5.

[cosmos schwarz]

whats the difference between 75w and 80w? this stuff has the limited slip additive in already and is cheap. says for use where GL5, 80W, 85W, 90 or 85W-90 limited slip oil is specified.yeah, i know 75w90 is specified for e30 rear diff's.

it was recommended by a friend who says it is listed at his store for use in bmw lsd's.

thanks if anyone can help, S3.91 w/m cover going in this weekend.

[cosmos schwarz]

this is what it says on the bottle.

LS80W-90 Limited Slip Gear Oil

High quality, mineral based, extreme pressure gear oil with friction-modifier for smooth operation of limited slip differentials

Service Classification: API GL5

should i take this back as its mineral based and it's slightly the wrong grade? what effect would it have on the diff if i used it.
i've read that some m3 owners use this stuff.