Rear differential issues??

ndpitch

Member
:
2014 CX-5 Touring
Hi there.

So I noticed a repeating sound coming from my wife's 2014 CX-5 Touring recently. We noticed the noise shortly after Mazda rotated the tires at an oil change at around 7,000 miles.

To me, it sounded like a break pad scraping against the rotor every time the tire made a revolution. The speed of this repetitive sound changed as the vehicle speed changed, and was independent of applying the brakes. Simply moving back and forward in the driveway was enough to reproduce this sound, so nevertheless it was clear that something was making a noise from the rear of the car every time the tire made a revolution.

I took it in, expecting them to make a quick adjustment to something minor, and we'd be on our way.

Wrong. We get a call about 8 hours later saying that they think something is wrong with the rear differential, and they're ordering the new parts. They put her in a rental and kept the car. It's now been over a week, and they're saying the parts they need are on back order. They're saying it might be another week before they even receive the parts they need. We're being given the runaround. First they said it would be a 2-3 day repair. Then they said they have the parts in as a critical status so they get them faster, and the warehouse says they have 29 of them. Then they say it's on backorder and that they "hope" the parts come in by the end of next week.

As if that wasn't infuriating enough, the real issue I have is that, assuming they even diagnosed the problem correctly, WHY would the rear differential on a 2014 Mazda CX-5 with 7,000 miles need replacement this soon?! This isn't a very good sign. Sure, it's under warranty, but it's a little unsettling when a brand new car that's driven very lightly is already having drivetrain problems. It also seems to be a strange coincidence that this noise cropped up right after the service shop rotated the tires. But of course you'll never get Mazda to own up to the possibility that they might have broken something when doing routine maintenance to a vehicle.

Has anyone out there heard of similar issues or experienced something like this yourself? Any suggestions? We're basically stuck at a standstill.
 
It might be related to this TSB:

TSB: 03-002/14

2013-2014 CX-5 - RATTLE / CHATTER NOISE FROM REAR DIFFERENTIAL

APPLICABLE MODEL(S)/VINS

2013-2014 CX-5 vehicles with VINs lower than JM3 KE ****** 391989 (produced before September 16, 2013)

DESCRIPTION

While driving at low speeds, some vehicles may exhibit a chattering/rattling type noise from the rear of the vehicle. A rear differential component, internal bearing noise, may be the cause.

Customers having this concern should have their vehicle repaired using the following repair procedure.

REPAIR PROCEDURE

1. Lift the vehicle. Refer to MS3 online (section 00-00 JACKING POSITIONS, VEHICLE LIFT (2 SUPPORTS) AND SAFETY STAND (RIGID RACK) POSITIONS).
2. Verify if the noise is heard from the rear differential component (A) when the wheel speed is approximately 3 to 6 mph (5 to 10 km/h).

3. Has the noise been verified?
Yes - Proceed to step 4.

No - This bulletin does not apply. Refer to MS3 online or Workshop Manual (section 03-03 NO.3 ABNORMAL NOISE AND/OR VIBRATION FROM COUPLING COMPONENT).

4. Contact MASH to obtain authorization to replace the rear differential component (including the coupling unit). Refer to MS3 online or Workshop Manual (section 03-14 REAR DIFFERENTIAL REMOVAL/INSTALLATION).
 
Geez... why so upset? They've found the problem, admitted that it is a problem, are fixing it, and they've given you a free loaner. What else do you want?

The dealer has no incentive to drag this out. You'll get your CX5 back with this fixed under warranty. Better to find this out now than get stuck on the side of the road somewhere when you're warranty has expired. You should be thanking them.
 
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I never drove my 2013 (which I recently traded with 55,000mi) like Grandma and I never had any drivetrain motor issue. Unlucky imo, and you don't want to rush them doing a job like that. It's already a pain just to lowear the rear subframe witht he differential ATTATCHED. Removing it requires you actually have to support the rear subframe independently because you can no longer use the diff as a jack point. You also have to disconnect a bunch of stuff, and there is some computer changes that have to be made to match some etching on your new diff. It's labour intensive, and parts like that are expensive and not just sitting in a dealers warehouse. I've messed around with the rear subframe on my cx-5 a lot trying to figure out an ideal situation for a lowered cx-5 (awd) and the rear sway bar/end links. It's a pain.
 
As if that wasn't infuriating enough, the real issue I have is that, assuming they even diagnosed the problem correctly, WHY would the rear differential on a 2014 Mazda CX-5 with 7,000 miles need replacement this soon?! This isn't a very good sign.

Personally, I would be more suspicious of why the symptoms occurred right after the service than worry about a bad differential. This isn't the first rear diff that's gone out on a Mazda (my wife's Miata had one replaced under warranty shortly after she got it in late '05, It's not a complicated job as the whole unit is replaced, not individual components.) These things happen!Sure, it's under warranty, but it's a little unsettling when a brand new car that's driven very lightly is already having drivetrain problems. It also seems to be a strange coincidence that this noise cropped up right after the service shop rotated the tires. But of course you'll never get Mazda to own up to the possibility that they might have broken something when doing routine maintenance to a vehicle.This is not Mazda you're dealing with (except indirectly), but an independent dealer.
BTW: You don't list your Touring as AWD, but I'm assuming it is. Correct?
 
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BTW: You don't list your Touring as AWD, but I'm assuming it is. Correct?

Yes it is. If this happened to my CX-5 I'd be happy that it was being fixed and didn't cost me anything.

Although highly unlikely, you'll never really know if rotating the tires in any way affected the rear diff. But who cares as long as they fix it?

The fact that there is a TSB about it indicates that at least some vehicles have this problem. It's much more likely that yours does and rotating the tires had nothing to do with this. It seems to me very unlikely there is any conspiracy going on here, but if it makes you feel better...
 
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Yes it is.
The fact that there is a TSB about it indicates that at least some vehicles have this problem.
Is this guy your next door neighbor or something? How do you know it's AWD, other than from his description of what the dealer is doing to repair it. I was just trying to be sure we were all on the same page here as far as the type of drivetrain we were discussing. Why would you answer this question for him? And...how can you be sure that the TSB referenced in post #2 has anything to do with the problem he's experiencing?
 
Yes it's AWD. It's frustrating because we got rid of a cx7 last year because we were constantly chasing problems in it. It was costing a ton of money in service. We traded it for the cx5, but now it's having issues. So it just seems like we're in a never ending loop of car troubles.

I checked the VIN and it's within the range of affected vehicles. I asked them to check to see if there were any TSBs out there for this, and they said there weren't. But it turns out there are I guess. Thanks for finding that! I'll probably print it off and bring it to them.

I just hope it actually is a defective rear differential and the new parts solve the problem.
 
I just had the same problem with the rear differential. It's my wife's CX-5, 2014. Last week the car displayed "AWD Inspection needed" or something like that on the dash. She never complained of any noise, and I never noticed anyting on the rare occasion I drove it. I made an appointment and brought it back to the dealer. The rear differential and some kind of vent need replaced. Lucky me, though. I was about 1,000 miles on the good side of the powertrain warranty. Love the car, but on the other hand, I am considering getting rid of it.
 
I just had the rear diff replaced as well. It fell under the TSB. Took 5 trips to the dealer to figure it out as the noise goes away when on a lift. They needed to put it on the alignment rack to find the noise and realize it was the diff. I have a little over 40K on my 2014 AWD.
 
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