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).
 
:
'21 CX-5 CE-T
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.

 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
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.
 
:
'16.5 CX-5 AWD
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.
 
:
'21 CX-5 CE-T
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.
 
Last edited:

Dino1956

Member
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: 20

Dino1956

Member
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?
 

Dino1956

Member
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.
 

skeptical

'21 CX-5 Signature
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...