2016.5 CX5 GT AWD...Transmission fluid change?

Officially: it’s a lifetime fluid. Here’s the used ATF analysis thread so you can determine whether or not you’d like to change yours.

 
There is none. Mazda calls the synthetic fluid good for the life of the trans. I have been changing mine every 30k miles because I tow.
 
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The fluid is only half of the answer. The other half of the answer, is the transmission. Noone truly knows how tolerant the SA transmission is of fluid spec changes. An example is some of the guns I work on.

Some of the M4 type rifles I mess with have properly sized gas ports for use with and without a suppressor. On those guns, if the gas tube and gas block and carrier gas key are not within spec, you WILL have malfunctions. On others, the manufacturer oversizes the gas port so that people can run trash ammo through them, without a suppressor, and the rifle will function with gusto no-matter what, to reduce warranty calls from the masses. These guns, I have used measured out of spec gas tubes, etc. on and they run absolutely fine.

So...is the SkyActiv a product with a narrow tolerance for fluid spec, or is it more like the latter example, where viscosity really isn't a huge player in the function of the transmission, comparatively, etc? I truly don't think anyone outside of Japan could answer that.
 
I'm also wondering about the change intervals for the transmission fluid, as well as the brake fluid and rear differential/transfer case fluids. Neither the 2015 manual nor the 2020 manual specify any sort of change interval, other than 'change the rear differential / transfer case oils if the car is submerged in water'.

My 2015 CX-5 (Touring) had almost 113K miles on it (almost 6 years old) before we traded it in very recently due to the passenger side curtain airbag deploying unexpectedly (front wheel hit curb after slipping on ice in neighborhood, no impact whatsoever to the body). We had been planning to keep it much longer, but we now have a 2020 CX-5 GT w/PP (35 miles, so new), which I absolutely love.

On my 2015, I had the rear differential fluid changed at 41,211 miles by the dealership, and again at 100,636 miles by my trusted independent mechanic. This same mechanic looked at the brake fluid and transmission fluid, stated they both looked great, and recommended I get them changed at 120K miles.

On the other hand, my husband last year purchased a used 2015 Nissan Rogue with 108K miles on it, which had never had the "lifetime" transmission fluid changed, and 3 weeks later it had a catastrophic transmission failure. (CVT; we knew the reputation for Nissan CVTs and their so-called "lifetime" transmission fluid going into the sale, but my husband really liked the Rogue)

So, I think the Mazda has a much better track record, but I'm still a little leary of trusting manufacturer recommendations for "lifetime" fluids. I did read the thread on analysis of the Mazda transmission fluid, which was very helpful.

So, do you have any solid opinions on the "lifetime" durability of the rear differential fluid, brake fluid, and/or transmission fluid, or links to appropriate threads? Thank you.
 
I’m happy changing the transmission fluid on my ‘13 CX-5 at 50k intervals based on my Blackstone report (you might have seen it under the separate ATF thread). Brake fluid is easier to determine: It should be changed based on water content, not mileage or appearance. You can buy a brake fluid tester on Amazon pretty cheaply. If it reads 2-3% water or greater you can change the brake fluid.

I don’t have a solid opinion on rear differential though. My ‘19 RAV4 is my first AWD vehicle and I’m going to follow whatever the severe service guideline is for that. My RAV4 also claims lifetime fluid for transmission and rear differential under “normal” use, but like 50 or 60k for severe service. We’ve got some big hills where I live and we often take gravel roads for weekend hikes so I’ll follow the severe schedule for peace of mind.
 
IMHO, Mazda may call them lifetime fluids or imply that they don't need to be changed for the life of the vehicle, but unless they are willing to foot the bill in the event of transmission repair/service for as long as the car is on the road (and out of warranty), there isn't much reassurance. I have a CX-9, and I don't tow or plan to carry very heavy loads that often, so I'll probably do fluid changes every 100-120k kms (~60-75k miles). This may be a little more involved for some people, but you can DIY (and we have many helpful resources here on the forum that show you how to DIY, if you're interested).

Transmission fluid guide
Another transmission fluid guide
Rear diff and transfer case guide
 
I’m happy changing the transmission fluid on my ‘13 CX-5 at 50k intervals based on my Blackstone report (you might have seen it under the separate ATF thread). Brake fluid is easier to determine: It should be changed based on water content, not mileage or appearance. You can buy a brake fluid tester on Amazon pretty cheaply. If it reads 2-3% water or greater you can change the brake fluid.

I don’t have a solid opinion on rear differential though. My ‘19 RAV4 is my first AWD vehicle and I’m going to follow whatever the severe service guideline is for that. My RAV4 also claims lifetime fluid for transmission and rear differential under “normal” use, but like 50 or 60k for severe service. We’ve got some big hills where I live and we often take gravel roads for weekend hikes so I’ll follow the severe schedule for peace of mind.
Thank you, Ruth, and Sm1ke. I think that is solid advice on the transmission and brake fluids.

Sm1ke, we're not really DIYers for car stuff, beyond changing wiper blades and air filters. Especially after reading about Digbick's ATF saga. I will leave that one to the professionals. :)

Ruth, the 2020 CX-5 manual doesn't mention change intervals for any of these fluids, not even under severe service. On our old CX-5, we did the Rear diff. fluid about every 50K miles, based on our mechanic's recommendation.
 
Mazda doesn't have a regulars change mileage value in the maintenance schedule. There is no reference to a "LIFE TIME" fluid so people should stop saying it is. Many vehicles today don't have a fluid change interval on ATs and often run to several hundred thousand miles without incident. Ed
 
I'm also wondering about the change intervals for the transmission fluid, as well as the brake fluid and rear differential/transfer case fluids. Neither the 2015 manual nor the 2020 manual specify any sort of change interval, other than 'change the rear differential / transfer case oils if the car is submerged in water'.
ATF change interval is decided by your own as different people have different opinion. Most people would agree that you’ll have more risk introducing problems changing the ATF after 100K miles, especially by ATF flush machine instead of drain-and-fill. Luckily Mazda’s SkyActiv-Drive 6-speed automatic can only do drain-and-fill unless the shop has hard-to-find special adapter to do the ATF flush.

My 2015 CX-5 (Touring) had almost 113K miles on it (almost 6 years old) before we traded it in very recently due to the passenger side curtain airbag deploying unexpectedly (front wheel hit curb after slipping on ice in neighborhood, no impact whatsoever to the body). We had been planning to keep it much longer, but we now have a 2020 CX-5 GT w/PP (35 miles, so new), which I absolutely love.
2015 CX-5 Touring with 113K miles has reliable SkyActiv-G 2.5L, but 2020 CX-5 GT with PP and 35 miles has a cylinder-deactivation-equipped SkyActiv-G 2.5L. Based on history CD is problematic for the long term, and there’s already a recall on the CD.

Wonder why you decided to trade in the 2015 CX-5 only because the side curtain airbag deployed?

On my 2015, I had the rear differential fluid changed at 41,211 miles by the dealership, and again at 100,636 miles by my trusted independent mechanic. This same mechanic looked at the brake fluid and transmission fluid, stated they both looked great, and recommended I get them changed at 120K miles.
Most of time you can’t tell the fluid quality just by looking. You can check the moisture level on brake fluid to decide if you need to change the fluid. On ATF a used ATF analysis is needed to tell if the ATF has lost its service life. I have doubts that your trusted mechanic actually checked the moisture level on brake fluid, and took time to access the ATF dipstick and actually “looked” the fluid.

On the other hand, my husband last year purchased a used 2015 Nissan Rogue with 108K miles on it, which had never had the "lifetime" transmission fluid changed, and 3 weeks later it had a catastrophic transmission failure. (CVT; we knew the reputation for Nissan CVTs and their so-called "lifetime" transmission fluid going into the sale, but my husband really liked the Rogue)
There’s a reason why a lot more Nissan Rogues than Mazda CX-5 sold in the US.

So, I think the Mazda has a much better track record, but I'm still a little leary of trusting manufacturer recommendations for "lifetime" fluids. I did read the thread on analysis of the Mazda transmission fluid, which was very helpful.
Sometimes too much information is not a good thing. ;)

So, do you have any solid opinions on the "lifetime" durability of the rear differential fluid, brake fluid, and/or transmission fluid, or links to appropriate threads? Thank you.
I personally will change (drain-and-fill) the ATF at 50K ~ 60K miles. I’m still debating if I want to take the ATF pan down、clean up the sludge on the magnetic、and replace the filter cartridge.
 
ATF change interval is decided by your own as different people have different opinion. Most people would agree that you’ll have more risk introducing problems changing the ATF after 100K miles, especially by ATF flush machine instead of drain-and-fill. Luckily Mazda’s SkyActiv-Drive 6-speed automatic can only do drain-and-fill unless the shop has hard-to-find special adapter to do the ATF flush.


2015 CX-5 Touring with 113K miles has reliable SkyActiv-G 2.5L, but 2020 CX-5 GT with PP and 35 miles has a cylinder-deactivation-equipped SkyActiv-G 2.5L. Based on history CD is problematic for the long term, and there’s already a recall on the CD.

I chose this vehicle based on its excellent suite of newer safety features, along with the good track record of our previous CX-5. No car is perfect. We also test-drove a RAV-4, and did not care for some of its issues. (Loud road noise/whine above 45 mph, very little head room for driver and passenger, no heads up display available on any trimline, and annoying interference from the lane keep assist while driving on the freeway, making it feel like we were fighting crosswinds unless the system was turned off.) I looked up "cylinder deactivation" on this website. I understand you have strong feelings about it. It doesn't bother me.

Wonder why you decided to trade in the 2015 CX-5 only because the side curtain airbag deployed?
1. I had no way of knowing if any of the remaining airbags were still functional.
2. The car was only worth about $7500, and it would have cost $10,000 to fix everything, per the dealership, based on their cost to obtain parts. Non-dealership mechanics told me they don't even touch the airbag system. I assume for liability reasons. I was definitely not interested in tackling the job on a DIY basis.

There’s a reason why a lot more Nissan Rogues than Mazda CX-5 sold in the US.
And what would that reason be?
I personally will change (drain-and-fill) the ATF at 50K ~ 60K miles. I’m still debating if I want to take the ATF pan down、clean up the sludge on the magnetic、and replace the filter cartridge.
Thank you for sharing your opinion on the change interval.
 
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And what would that reason be?
Although your husband really liked the Nissan Rogue, I’m personally not interested in Rogue mainly on reliability concerns. The reasons why a lot more Rogues sold in the US, IMO, are lower selling price、bigger interior、more features (such as individual tire pressure display right in the dash)、and available 3rd-row seating.

2017-nissan-rogue-safety-tire-pressure-monitor-large.jpg
 
Although your husband really liked the Nissan Rogue, I’m personally not interested in Rogue mainly on reliability concerns. The reasons why a lot more Rogues sold in the US, IMO, are lower selling price、bigger interior、more features (such as individual tire pressure display right in the dash)、and available 3rd-row seating.
Thank you for clarifying. That makes sense. To each his/her own.
 
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