New CX-5, high pitched whine at 80 km/h (50 mph)

Has anyone tried to hear the noise and NOT heard it? If not, then it's probably a drivetrain issue. If most people don't have the noise I'd suspect faulty weather striping (re: pdf).
 
Just noticed this noise, and can't un-hear it at any speed.

It's almost like a ground loop noise, but it follows vehicle speed, not engine speed.

Found a post on Reddit where the vehicle was diagnosed with transmission issue, and transmission will be replaced under warranty.

 
Just noticed this noise, and can't un-hear it at any speed.

It's almost like a ground loop noise, but it follows vehicle speed, not engine speed.

Found a post on Reddit where the vehicle was diagnosed with transmission issue, and transmission will be replaced under warranty.

I've heard a much fainter whine than in that clip coming from somewhere between the back seat and the rear. I have to be listening for it to hear it. I'm regarding that as normal.
 
I've heard a much fainter whine than in that clip coming from somewhere between the back seat and the rear. I have to be listening for it to hear it. I'm regarding that as normal.

I'm the OP here and the sound I was describing also seems much fainter than in the r/mazda video that @teddymac posted.

For what it's worth, the sound seems to have become quieter as the vehicle has broken in. It's quieter but still noticeable at 80 km/h and somewhat less so at other a couple of other speeds. And I don't notice it on deceleration anymore.

My sound definitely comes from the front and I still think it's transfer case related. @HardRightEdg's experience sounds similar to mine but perhaps from the rear differential.

Has anyone with this issue changed their transfer case or differential oil and, if so, was there any change?
 
Probably zero help, so apologies in advance, but didn't some recent year CX5s have an issue/TSB for something to do with either the cowling near the windshield or the windshield seal itself, where it would make a whine or high pitched noise at highway speeds and above? Just mentioning it in case maybe it applies to one of the situations here.
 
There it was, very faint, at 50 mph with the radio off, AC running on low, on a smooth blacktop where tire noise would not disguise it. Unlike the OP, it went away when I let all the way off the gas. It came back upon very mild reacceleration. I could easily see how many drivers would not take note of it--that's how faint I found it to be.

This is classic hypoid gear whine caused by imperfect tooth engagement. I forget what causes it to go away on trailing throttle, but maybe it is the pinion gear too far "forward". Faint noise is not harmful to the gears, just noisy.
 
Just noticed this noise, and can't un-hear it at any speed.

It's almost like a ground loop noise, but it follows vehicle speed, not engine speed.

Found a post on Reddit where the vehicle was diagnosed with transmission issue, and transmission will be replaced under warranty.

Brought the car in, they drained the transfer case, and there were shards of metal on the plug. So a replacement is on the way. Shpuld be fixed within a week... surprisingly, given the state of the world.

Side note: In the mean time they gave me a non turbo as a loaner. Not to be picky at all, but I must say that I'm glad I got the turbo. The start of the acceleration is the same... The rest is like mashed potatoes with no dressings... Just vrrrbleeeeehhhhhhh.
 
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This is an old post, but I'll give it a shot. Same issue with MX- NC 2008.
This is an My VIN is one of the cars from a Differential Service Bulletin. See attached Bulletin. Bought my NC1 used. Two owners before me. Called up Mazda and got Service History. First owner got Diff Oil changed at 77.000 miles but I still have the whine when I hit 50 mph. I will get Diff oil changed again since it is now at 114,000 miles. It's not loud but there right at 50 mph like clock work. Here is a video I made.Fast forward to 45 seconds on video.Hard to hear on Video. Listen closely.

 

Attachments

  • Mazda Service Bulletin Whining Noise from Diff.pdf
    68.6 KB · Views: 168
Brought the car in, they drained the transfer case, and there were shards of metal on the plug. So a replacement is on the way. Shpuld be fixed within a week... surprisingly, given the state of the world.

Side note: In the mean time they gave me a non turbo as a loaner. Not to be picky at all, but I must say that I'm glad I got the turbo. The start of the acceleration is the same... The rest is like mashed potatoes with no dressings... Just vrrrbleeeeehhhhhhh.
So it was the Diff or Tranny?
 
My noise is a bit different. Only on acceleration. The second I remove my foot from pedal, the noise is gone. Well at least you got yours fixed. Thanks.
 
I have the noise in my 2021 Sig. I have been considering have the dealer diagnose it. It's annoying. Glad I found this thread...
 
My noise is a bit different. Only on acceleration. The second I remove my foot from pedal, the noise is gone. Well at least you got yours fixed. Thanks.
I just noticed my 19 signature doing this around 80km/hr (50mph) there’s a very faint whine that is alleviated by easing off the gas.

As soon as I step slightly on the gas, the sound comes back.

not really noticeable at other speeds which is bizzarre.

Did you figure out what the issue was?
 
is this your first turbo car? just asking. Usually the turbo has a slight whisling sound when you accelerate. On Mazda you could hear it inside, other cars it depends where it is.
 
is this your first turbo car? just asking. Usually the turbo has a slight whisling sound when you accelerate. On Mazda you could hear it inside, other cars it depends where it is.

If you’re talking to me, yes - it is my first turbo. But, I’m literally hearing what some other people here are Saying they’re hearing - and it only starts between 50 and 60mph - so just checking.

I am familiar with turbo-whine tho.
 
Yes indeed few different noises :)
one is the whine from the turbo the other is the weather strip at higher speed and the third is the transmission if it goes bust. At least those that I know of.
if you are easing the gas its isually the turbo.
 
This noise is coming from the transmission caused by an input shaft bearing. Report it to your dealer and hopefully Mazda approves a replacement. Some have managed to get a replacement with one try and for others it took multiple tries.
 
This noise is coming from the transmission caused by an input shaft bearing. Report it to your dealer and hopefully Mazda approves a replacement. Some have managed to get a replacement with one try and for others it took multiple tries.
Can you talk a little more about this "input shaft bearing" issue? My 22 CX5 non-turbo has a very clearly heard coil whine around 45-50 mph. I'm thinking I may need talk to my dealership about it.
 
This noise is coming from the transmission caused by an input shaft bearing. Report it to your dealer and hopefully Mazda approves a replacement. Some have managed to get a replacement with one try and for others it took multiple tries.
This problem, if that is what it is, goes back to 2013 models and it still is coming up. I had a trans replaced on my 2014 because of this. Can't believe it's still rearing it's head.
 
Can you talk a little more about this "input shaft bearing" issue? My 22 CX5 non-turbo has a very clearly heard coil whine around 45-50 mph. I'm thinking I may need talk to my dealership about it.
I've taken my car 5 times to the dealer so far as the noise keeps getting worse. The technicians confirmed the noise is coming from the transmission, however Mazda is deeming it as normal operation of the vehicle.

This is beyond disappointing, considering the car has a very distinct high pitched whining noise coming from the transmission during acceleration or deceleration at specific speeds.

I've included some recent recorded videos for reference:
 
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