I have a 2004 530D auto. When I am driving reasonably quickly, I sometimes get a "chirp" or low sqeak from somewhere in the drivetrain when it changes down a gear under stress. It is particularly noticable if I kick down on a bend for example. It doesn't happen every time and there is no feeling of loss of power (like a slipping clutch for example). It usually coincides with the boost of the turbo cutting in.

I wonder if this is some sort of torque limiter doing its job or if there is a problem somewhere. I am reluctant to get BMW involved unless there is a reproducible fault which I can demonstrate every time.

Any ideas anybody? Thanks.

 

This is normal or should I say all the 3.0D's do it. It's to do with the vanes of the turbo. My 530D does it and my 4 year old X5 3.0D also does it. One would expect that 4 years later they would have come up with a fix to stop this turbo chirp.

So, no there is no problem and dont waste your time with BMW.