I recently had my rear brakes done at the dealership, and on a couple of occasions now have had a loud whine occur when I reach ~140mph.
Prior to the brake job I had the car significantly faster with no noise to speak of.
I am hoping to attend some open track events in the near future, but would ideally like to get this sorted before then.
I took it the dealer and asked them to take a look, but they let the car sit for 6 days, killed the battery* and didn't find anything and charged me 670 for the pleasure of replacing the battery they killed.
Much appreciate any advice on the suspected cause of the whine.

Cheers,
Diallo

If the timing isn't clear in the video, I was still accelerating when the noise began. I began braking after I heard the noise.

*The dealership said they would see what they putzed on the brake job and pull for the check engine light in April.
Not wanting to spend 2 months with a CEL with an unknown cause, I pulled the code using a usb dongle.
Based on my readings here I knew there was a high likelihood there would be a battery drain.
There was, but due to me getting someone higher up in the dealership to make some calls the time they could see me went from sometime mid-april to 'today', so I figured rather than disconnecting the battery, the circuit would reset when they pulled the code. I told them when I dropped off the car there was a battery drain, and asked they they pull the code and stop the battery drain. They said no problem.
They then let the car sit for 6 days, when I said I was coming in today to pickup my car they told me my battery was completely dead and had to be replaced.

 

Try applying the brakes (lightly will do) when you hear the noise and see if the sound changes or goes away. That seems like the most likely suspect.
If not, it could be a heat shield, but the sound seems different to me.

 

Does not sound like a "whine" to me. Unlikely related to the transmission.
Sounds more like soem thing scraping. I would guess that at high speed the car sits down (or lifts up?) in such a way that contact is made between loose or closely (mis)aligned parts.
I would focus on the brake job as the culprit. Logically it was the last thing done to the car.

 

Thanks, I've tried application of brakes at different speeds and with varying firmness, but have been unable to duplicate the sound at more moderate speeds.

 

Thanks for the idea, I hadn't considered the aerodynamic implications of the speed.

 

Something like a heatshield that was moved/knocked during brake job?

 

Probably go away once you accelerate past 140mph!!!

 

The test is not to see if you can create the sound with the brakes - it's to see if the sound goes away if the brakes are applied. Something like a sticky caliper of warped disk could be causing the noise, but will likely stop if you (even lightly) apply the brakes. Of course, if it's much of a warped disk, you probably also feel it when the brakes are applied. Time for another speed run (which your dealer may or may not attempt).

 

Ok, gotcha.

It seems to be speed dependent. I did another run this morning before seeing this, but looking at the video the whine now seems to start at a lower speed. It started at 133, as reported by draggy, continued as I got off the gas, and onto the brakes (peak speed 137) and persisted until my speed dipped below 127.

 

Where do you get drive those peeds??

 

I would be careful posting videos of you going over 130 MPH on public roads, and what appears to be residential areas, unless you are on the unrestricted section of the Autobahn (or Mexico). I would bet your dealer is not going to test the car at those speeds either.

DC

 

Appreciate the advice, I've changed the videos from public to unlisted (only accessible via the links).
I'd say I don't have a lot of confidence in the local pd (See videos of kids doing donuts in the CBD with a passenger hanging out the moonroof with an AK), but murphy's law suggests I err on the side of caution.
I will take the vids completely off line in a week or when/if I can get to the bottom of the the sound.

 

The Mexico border isn't that far from NOLA ;-)

 

Sounds like something resonating in the wind (like a reed.) I don’t know what it sounds like when folks have had loose rubber seals under the hatch.

 

I think you might be onto something!
It doesn't sound mechanical to me, as you say more like a reed in the wind.
Never had the loose hatch seal noise myself but worth checking.

 

The rubber seal issue sounds totally different. Sounds like something clicking or a bug scratching around under the upholstery...Just FYI.

DC