2017~2025 Rear differential failure
- Thread starter n0m0remazda
- Start date
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- W WA
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- 2024 CX-5 Premium
Rear diff failure is not a common issue with these cars.
Cx5 2017 manual does not list any service maintenence for fluid at any number of miles, only when vehicle is submerged, which it never was (CO and PA). Regular mazda dealership visits, and never once mentioned about rear differential oil replacement or issue until now. Why should the customer be responsible for Mazdas lack of accountability for proper maintenance. A cursory online search shows that it is an issue. The customer rep also did state it was an issue shes been getting calls about. The mazda dealership guy did admit that there was no maintenance details for this problem.
Yours is basically the first I've seen on this forum and I've been around since 2015. There was a post once but the car was driven through deep water.
If it was a problem I'm pretty sure there would be lots of posts on this forum.
- :
- W WA
- :
- 2024 CX-5 Premium
My dealer suggested replacement of the diff fluid on my 2020 at around 50K miles. I complied with his suggestion.
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- W WA
- :
- 2024 CX-5 Premium
@n0m0remazda how many miles on your CX5 when the diff failed? Do you know if the fluid level was ever checked? Did you do any towing (boat, trailer, etc.) with it?
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- Canada
I have had to get my rear differential replaced at 113k kms (70k mi) on my 2018 CX-9. I tried to take really good care of that car, but I had not replaced the rear diff fluid when this all happened - although I don't think it would have made any difference. In my case, the car saw very, very little "offroading", just a short climb up a dirt road here and there. Never towed anything, and I never pushed the car hard in the snow. 95% city/highway driven.
I maintain that a rear diff failure is rare, but not unheard of. There have been a few cases reported on Reddit and Facebook, and 2 or 3 other cases mentioned here besides mine (2 other CX-9s and 2 CX-5s, including yours).
For reference:
I was able to get Mazda Canada to assist with the repair cost after some back and forth, and a lot of persistence and patience on my part. I think it helped that I never allowed my communication with them to get too "heated" - I tried to remain firm, logical and reasonable the whole time.
There is absolutely a management team or manager that these reps report to. The first time I asked for an escalation, I was also told that no manager would be able to help me. If its worth it to you, be persistent. If they say no, change your "angle" a little bit, explain your reasoning for wanting to speak to someone higher up the chain, and articulate your expectations with reasonable support.
For example, I made the case that the rear differential is expected to last the lifetime of the vehicle, since there is no fluid change interval, only a visual inspection (that would not reflect any potential internal issues). And, when dealerships perform the inspection after an oil change, "rear differential fluid inspection" is not an item that is checked.
Hope you can get some assistance with the repair.
I maintain that a rear diff failure is rare, but not unheard of. There have been a few cases reported on Reddit and Facebook, and 2 or 3 other cases mentioned here besides mine (2 other CX-9s and 2 CX-5s, including yours).
For reference:
I was able to get Mazda Canada to assist with the repair cost after some back and forth, and a lot of persistence and patience on my part. I think it helped that I never allowed my communication with them to get too "heated" - I tried to remain firm, logical and reasonable the whole time.
There is absolutely a management team or manager that these reps report to. The first time I asked for an escalation, I was also told that no manager would be able to help me. If its worth it to you, be persistent. If they say no, change your "angle" a little bit, explain your reasoning for wanting to speak to someone higher up the chain, and articulate your expectations with reasonable support.
For example, I made the case that the rear differential is expected to last the lifetime of the vehicle, since there is no fluid change interval, only a visual inspection (that would not reflect any potential internal issues). And, when dealerships perform the inspection after an oil change, "rear differential fluid inspection" is not an item that is checked.
Hope you can get some assistance with the repair.
I'd suggest to look for a rebuilt rear differential (readily available) and install it privately. I'd estimate an all-in cost around USD1500. I just had this very thing occur on a 2014 CRV, and Mazda uses very similar AWD technology.
Remember - OEM maintenance recommendations are meant to get you to the end of the warranty, and no further. Its actually profitable if failures occur after warranty expiration. There is no such thing as 'lifetime' lubricants - they all break down. Changing brake fluid, transmission fluid, coolant, rear differential fluid, etc., is a good practice.
Don't forget transfer case gear oil too.
For my 2016.5 CX-5 GT AWD, the Owners Manual indicates the following maintenance servicing for the differential:
But, interestingly, the 2017 CX-5 only indicates the following ... for normal and severe driving conditions, for USA, Canada and Mexico:
Took a look at the 2022 CX-5 manual as well. It, too, only indicates the "submerged in water" maintenance warning.
If out of warranty, I can see how Mazda might point to their maintenance specifications and not want to cover the repair.
My own 2016.5 is almost 10yrs old. At 135Kmi, it has had the transm/transf/diff fluids changed out twice, now, and this coming year will be done a third time. When I acquired the car (pre-owned), I noticed in the manuals the between "normal" and "severe" service Schedules for maintenance. Wanted to err on the side of caution. Particularly with so many CX-5 owners choosing to change the drive line fluids at 30-50Kmi intervals. Doesn't help with your 2017, I know.
*5 If the vehicle is operated primarily under any of the following conditions, replace the rear differential oil at every 48,000 km (30,000 miles).
a) Towing a trailer or using a car-top carrier
b) Driving in dusty, sandy or wet conditions
c) Extended periods of idling or low speed operation
d) Repeated short trips of less than 16 km (10 miles)
*6 If this component has been submerged in water, the oil should be replaced.
a) Towing a trailer or using a car-top carrier
b) Driving in dusty, sandy or wet conditions
c) Extended periods of idling or low speed operation
d) Repeated short trips of less than 16 km (10 miles)
*6 If this component has been submerged in water, the oil should be replaced.
But, interestingly, the 2017 CX-5 only indicates the following ... for normal and severe driving conditions, for USA, Canada and Mexico:
* 5 If this component has been submerged in water, the oil should be replaced.
Took a look at the 2022 CX-5 manual as well. It, too, only indicates the "submerged in water" maintenance warning.
If out of warranty, I can see how Mazda might point to their maintenance specifications and not want to cover the repair.
My own 2016.5 is almost 10yrs old. At 135Kmi, it has had the transm/transf/diff fluids changed out twice, now, and this coming year will be done a third time. When I acquired the car (pre-owned), I noticed in the manuals the between "normal" and "severe" service Schedules for maintenance. Wanted to err on the side of caution. Particularly with so many CX-5 owners choosing to change the drive line fluids at 30-50Kmi intervals. Doesn't help with your 2017, I know.
N7turbo
2023 CX-5 2.5T ... 2024 MX-5 RF GT
Not understanding this being a bad thing for a differential.
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