Sounds like wind noise. Are all your jack pads in place?

Not sure why it would do it intermittently if it was wind noise.

No one has experienced this?

I'm in the same corner as edjack...a missing jack pad produces that type of sound...plus it's pretty easy to ascertain :thumbup:

Simple way to find out: crawl under there and make sure all four are firmly in place.

Will do when I get home. Will it be obvious what I'm looking for?

Yes, there rubber pads on the sills that you place the jack into to jack the car up. So four of them just behind/infront of the wheels.

May be intermittent due to wind direction. A 2 minute $0 job to check, so best starting point.

do m5's have jackpads? i know they dont actually have jacks.

Didn't look like any of the jacking points had covers. Here are pictures of the front ones:

Right (area where I'm hearing noise):



Left:

As a side note, does this M5 clutch have the little valve like my e90 where it slows engagement on an aggressive release to save wear/tear on drivetrain?

I listened to my youtube again, and I can see why the first thought was wind noise/whistling. In person, it sounds more mechanical. Sort of like the vibration you get when you rub your finger around the top of a wine glass (but more metal on plastic/plastic on plastic). And it baffles me because it comes and goes.

Was slightly cooler out this morning and it didn't happen. This is going to drive me crazy.

Well, this is fun. I just threw the P0491 secondary air injection system SES code. Two days into owning the car. The previous owner said he never had an issue with the code. After doing some research, it seems as though it is still OK to drive with this error code due to CBU.

What I'm wondering though... could that noise I'm hearing be the air pump having issues (not pushing enough air through an already partially clogged system), which is what is throwing the code?

This one I can answer -- No, the E39 M5 did not have the Clutch Delay Valve (CDV)

Here's a thread on that code: http://www.forums.bimmerfest.com/showthread.php?p=3766679&highlight=

As a side note, does this M5 clutch have the little valve like my e90 where it slows engagement on an aggressive release to save wear/tear on drivetrain?

Click to expand...

Thanks for the info and the link.

Most of what I've read says replacing the pump and valve ($500 in parts alone) usually doesn't remedy the issue. I'll poke around to see if a vacuum line is ripped, but since the squealing noise I'm hearing is even when the car is warm (i.e. the secondary air injection shouldn't be functioning, right?), I'm thinking the noise isn't the pump.

Edgy36-39 said:

This one I can answer -- No, the E39 M5 did not have the Clutch Delay Valve (CDV)

Here's a thread on that code: http://www.forums.bimmerfest.com/showthread.php?p=3766679&highlight=

Click to expand...

Cover those holes in the photos with duct tape and see if the sound goes away. Worked for me. At that point you have to decide if you want to replace the jack pads or just leave the tape.

I put some awesome grey duct tape over the front jack points this evening. Driving around, I didn't hear the noise, but I'm not 100% convinced that I solved the problem since the conditions were cooler today than they were when it last did it.

I have the same exact annoying sound in my 2000 540i. Driving me crazy. Ever figure it out?

Check the dust covers on the front brake rotors. I had a rock in there made a noise but some how not all the time.. Also check for a stuck caliper all that stuff ect ect