Mystery Diff Noise

[KDS]

Over the past few months I've been hearing a strange sound coming from the back end (I assume the diff). Sort of a ghostly "woooooo" sound. It's engine speed related and disappears when the clutch is in. Any thoughts on what it is and what should be done about it?

[Strawb]

Over the past few months I've been hearing a strange sound coming from the back end (I assume the diff). Sort of a ghostly "woooooo" sound. It's engine speed related and disappears when the clutch is in. Any thoughts on what it is and what should be done about it?

iv been haveing this type of trouble on my car i thought it was the diff but the sound doesent go away once the cluch is in. it only happends when turning right so im thinking its the wheel bearing, does the noise change when you turn corners as well

[Chris-W]

If it stops with the clutch pedal pressed I'd say it was the thrust bearing.

[KDS]

does the noise change when you turn corners as well

Nope, I notice the noise consistently--corner or no corner. I definitely stops when the car is coasting in neutral.

Chris, is the thrust bearing what we North Americans might call the throw-out bearing?

[Brianmoooore]

Chris, is the thrust bearing what we North Americans might call the throw-out bearing?

Same thing.

[Brianmoooore]

E30 diffs commonly develop a whine with age, but go on for many tens of thousands of miles with no ill effects.