Strange noise from rear of vehicle when driving

[CX5-NJ]

I have 2015 CX-5 with 1,600 miles on it, and I have noticed a noise coming from the rear end. It sounds like a honing type noise. At first I thought my rear hatch door might have not been closed all the way, but that was not the case. I am not sure if it's something wrong with the
rear end itself of something with the tires. Anyone else experience this type sound? Thanks!

 

[deepfriedsushi]

Bring it to the dealer?

Does the noise change pitch or volume with speed? Or is it a constant sound?

 

[CX5-NJ]

It's going back to the dealer on Wednesday morning. The noise seems to get more pronounced at higher speeds.

 

[Skorpio]

I haven't experienced it on my CX-5, but similar noises many times on other vehicles. Humming noises in the rear, getting louder with speed usually indicate chopped/feathered tire wear, rear differential gear noises, or rear wheel bearings. All of which should not be happening at 1,600 miles.

 

[minnesotaart]

Do you have a roof rack with cross bars? Possible source.

 

[CX5-NJ]

Yes, I do have a roof rack with cross bars. How would that effect the noise coming from the rear?

 

[dnichols021161]

I just bought a 2015 CX-5. I have just over 500 miles on it.
I too have a strange "honing" type noise that seems to come from the passenger side rear.

Interestingly, I never noticed it before I has the roof rack and cross rails installed. I supposed they might be the root cause, but it sounds to me like the noise is coming from below the vehicle. I was thinking more along the lines of tire noise or similar.

 

[MikeM.]

The CX-5 is relatively smooth and quiet as would be expected for a new, state of the art car..

If yours is not, take it to the dealer for diagnosis.

 

[BillofMass]

l am hearing the same sort of hum since installing cross bars. But only between 30 and 40mph. Will try sliding them to a different position or removing completely to confirm the source of the hum.

 

[123373]

l am hearing the same sort of hum since installing cross bars. But only between 30 and 40mph. Will try sliding them to a different position or removing completely to confirm the source of the hum.

If your not using the racks often, slide both of the as far rearward as possible. This will eliminate any wind noise and help gas mileage as well.

OP, On the sound you are hearing does it go away when you coast at the speeds it most noticeable? If not than wheel bearings could be the culprit. If so could be just exhaust growl.

 

[BillofMass]

Turns out that the cross racks were not tightened when mounted by the dealership. So l just slid them back and tightened both down. Problem solved, no more humming. Thanks for your response.

 

[mazdman]

It's the rear diff.

My wife's 2015 CX-5 GT AWD w/ just 6,500 or so miles had a weird clicking noise that I heard in the mall parking lot that was speed dependent and sounded almost like a stone btw the dust shield and one of the rear rotors. I checked everything out and it was OK. Apparently, there was a bad batch of diffs used in the 2014's and were supposedly caught before install into any 2015's. NOT!. My 2015 was the 7th rear diff replaced according to the tech.

Got to admit though, since relocating to a new state/city w/o the mega dealers, who focus on many brands and sales not service, the tiny Mazda only dealer who is just 5 miles from my new house, allowed me to watch them diagnose the problem and promptly replaced the rear diff w/o screwing anything else up and did a full detail inside and out. This is high praise coming from me as I've been an engineer in the auto industry for over 30 years and am very particular about my vehicles. I also had the left passenger lock assy replaced due to it squealing all the time. However, the noise occasionally is heard from the other door locks on the CX-5 and my CX-9 GT AWD w/ only 15,000 miles also occasionally makes this sound also. I guess it's just one of the things that Mazda can't get right. BTW, my pristine one owner 1994 RX7 w/ only 24,000 miles makes no lock noises at all, however, the list of upgrades to many other sub-par components on this car is pretty long.

Guess they just built some better components over 20 years ago! LOL!

I have 2015 CX-5 with 1,600 miles on it, and I have noticed a noise coming from the rear end. It sounds like a honing type noise. At first I thought my rear hatch door might have not been closed all the way, but that was not the case. I am not sure if it's something wrong with the
rear end itself of something with the tires. Anyone else experience this type sound? Thanks!

 

[mazdman]

My bad, guess I should have read further! Glad your's was just the roof rack!

It's the rear diff.

My wife's 2015 CX-5 GT AWD w/ just 6,500 or so miles had a weird clicking noise that I heard in the mall parking lot that was speed dependent and sounded almost like a stone btw the dust shield and one of the rear rotors. I checked everything out and it was OK. Apparently, there was a bad batch of diffs used in the 2014's and were supposedly caught before install into any 2015's. NOT!. My 2015 was the 7th rear diff replaced according to the tech.

Got to admit though, since relocating to a new state/city w/o the mega dealers, who focus on many brands and sales not service, the tiny Mazda only dealer who is just 5 miles from my new house, allowed me to watch them diagnose the problem and promptly replaced the rear diff w/o screwing anything else up and did a full detail inside and out. This is high praise coming from me as I've been an engineer in the auto industry for over 30 years and am very particular about my vehicles. I also had the left passenger lock assy replaced due to it squealing all the time. However, the noise occasionally is heard from the other door locks on the CX-5 and my CX-9 GT AWD w/ only 15,000 miles also occasionally makes this sound also. I guess it's just one of the things that Mazda can't get right. BTW, my pristine one owner 1994 RX7 w/ only 24,000 miles makes no lock noises at all, however, the list of upgrades to many other sub-par components on this car is pretty long.

Guess they just built some better components over 20 years ago! LOL!

 

[Nomaziyane]

I drive a CX-5 Active Red 2016 model. When I drive, there's an unknown sound at the back. Anyone experience this sound between the wheels and rear?