Advice on rear differentials!!

[ken.hau@xxxxxx]

Hello All,

Can someone please tell me what ratio diff. should be on a M3 E30 91
convertible and how can I identify that it is the correct one. I have
just
had it replaced and it is making a muted roaring noise @ cruising speed
that
is audible from the cabin which turns into a muted whinning noise @
motorway
speeds, it is bearable but is this normal? Does a LSD diff. make more
noise
than a non-LSD diff.? Or could it be my rear wheel bearings?

Ken

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