Last fall, a noise developed in the rear of my 2014 CX5 GT, which I interpreted as tire noise, since the OEM Toyos (225-55-R19) were down to about 4-32nds and the wear was a bit uneven. This was only after approximately 42,000 km on the Toyos, which I have since replaced, see the thread in the Wheels-Tires area for my initial review. I have a set of winter tires also; they currently have 24,900 km on them, that is why there is only 42,000 km on the Toyos.
The noise persisted after installing the winter tires last December, and it got a bit worse over the winter. I mentioned this to the dealer, but in all fairness to them, I explained that I interpreted the noise as a rotational growl/whine and told them I was certain it was tire related and never asked them to look into it further. In April, I had my Toyos re-installed hoping to get one more season out of them. Over the next few weeks, the noise got worse (almost unbearable at highway speed), so I decided to buy new all seasons. The dealer matched a Canadian Tire sale on the Pirelli P7’s and installed them in early May. I also asked them to check the alignment, thinking that was perhaps one of the reasons for the excessive noise.
I received a call later in the day from the service department. After installing the tires and checking the alignment (which was actually good on all four), they took it for a drive and discovered that the noise was still there. Back in the shop, they found the noise in the rear differential. After a bit of back and forth with Mazda Canada, it was decided to replace the unit under warranty. Although the CX5 was beyond the standard 3-year warranty, the 5-year power train warranty was still valid. According to the dealer, it would have cost about $1,700 to replace ($1,200 in parts). Apparently that was the first CX5 they had heard of that needed the rear diff replaced. If I recall correctly, the service manager said that a seal was gone.
I have no idea why the failure happened, I expect that it was an anomaly. I do not drive the vehicle off-road, just the normal wear and tear of Canadian winters. I don’t think the rear diff was ever submerged, either. I absolutely love my CX5, it has performed flawlessly and I still make excuses to go for a drive, even after 3 years of ownership. I usually don’t post in these forums (check my post count), and tend to use the forum as an information source, but I thought I would share this experience.
And yes, the CX5 is quiet again, just like new with the new rubber!
The noise persisted after installing the winter tires last December, and it got a bit worse over the winter. I mentioned this to the dealer, but in all fairness to them, I explained that I interpreted the noise as a rotational growl/whine and told them I was certain it was tire related and never asked them to look into it further. In April, I had my Toyos re-installed hoping to get one more season out of them. Over the next few weeks, the noise got worse (almost unbearable at highway speed), so I decided to buy new all seasons. The dealer matched a Canadian Tire sale on the Pirelli P7’s and installed them in early May. I also asked them to check the alignment, thinking that was perhaps one of the reasons for the excessive noise.
I received a call later in the day from the service department. After installing the tires and checking the alignment (which was actually good on all four), they took it for a drive and discovered that the noise was still there. Back in the shop, they found the noise in the rear differential. After a bit of back and forth with Mazda Canada, it was decided to replace the unit under warranty. Although the CX5 was beyond the standard 3-year warranty, the 5-year power train warranty was still valid. According to the dealer, it would have cost about $1,700 to replace ($1,200 in parts). Apparently that was the first CX5 they had heard of that needed the rear diff replaced. If I recall correctly, the service manager said that a seal was gone.
I have no idea why the failure happened, I expect that it was an anomaly. I do not drive the vehicle off-road, just the normal wear and tear of Canadian winters. I don’t think the rear diff was ever submerged, either. I absolutely love my CX5, it has performed flawlessly and I still make excuses to go for a drive, even after 3 years of ownership. I usually don’t post in these forums (check my post count), and tend to use the forum as an information source, but I thought I would share this experience.
And yes, the CX5 is quiet again, just like new with the new rubber!
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