How to completely disable cylinder deactivation?

Well, not yet. The kinds of issues you'd typically see from cylinder deactivation crop up 10~ years into ownership. So, you likely wouldn't see any issues yet.
That's a comical reply. All cars start having trouble with things by 10 years, but usually more like around 5 or 6 years.
 
Apparently, the car will not deactivate cylinders while it thinks it's in need of service. So, from now on, every time I get my oil changed, I'm just gonna set the interval for that same day, the dash lights will come on to remind me "I need service", and cylinder deactivation will apparently stay off.

I also think it's probably easier to just leave the service reminder up all of the time, but disable the service reminder on the dash with a tune, than it is to go through the entire process of disabling cylinder deactivation entirely.

Best of both worlds, perhaps? I'll just use Google Calendar to remind me when I need service instead.
Please confirm this using the infotainment menu cylinder deactivation display while cruising.
 
Please confirm this using the infotainment menu cylinder deactivation display while cruising.
I was gonna ask the same question.

But I am not so sure that I'd like have a "service soon" type notification constantly on my dash. And what if something that needs immediate attention pops up but the dash already displays "service soon"? How would an average Joe?
 
Apparently, the car will not deactivate cylinders while it thinks it's in need of service. So, from now on, every time I get my oil changed, I'm just gonna set the interval for that same day, the dash lights will come on to remind me "I need service", and cylinder deactivation will apparently stay off.

I also think it's probably easier to just leave the service reminder up all of the time, but disable the service reminder on the dash with a tune, than it is to go through the entire process of disabling cylinder deactivation entirely.

Best of both worlds, perhaps? I'll just use Google Calendar to remind me when I need service instead.
(y)🤓brilliant ....if this works its awesome-thanks for posting
 
All this potential wear and tear yet Mazda does not have a scheduled fluid change for transmissions. Or dip stick. When I asked about there being no dip stick the dealer said life time fluid.
The dipstick is under the air box. And you have to read it with the vehicle running and at a certain temperature. Accessing it with the airbox still in place is tricky so I won't say it's "easy", but it is there. You can drain and fill the fluid all you want, the fill port is there, the drain plug is there.

They won't say it, but "life time" for them means the extent of the powertrain warranty. For my the lifetime of the car will be 20+ years and 300k miles or so. I've gotten into the habit of performing drain / fills every 30-40k miles. I'm about to hit 150k and plan to pay a shop to drop the pan and replace the internal filter along with whatever fluid replacement.

CD is purely a CAFE thing. It’s not very impactful to individual owners in terms of fuel economy. Same thing with the “lifetime fluid” in the transmission. The EPA gives Mazda a CAFE credit for each vehicle with a sealed transmission.
See above. Unless something changed in CX-5 design recently, it is NOT a sealed transmission.
 
Last edited:
The dipstick is under the air box. And you have to read it with the vehicle running and at a certain temperature. Accessing it with the airbox still in place is tricky so I won't say it's "easy", but it is there. You can drain and fill the fluid all you want, the fill port is there, the drain plug is there.

They won't say it, but "life time" for them means the extent of the powertrain warranty. For my the lifetime of the car will be 20+ years and 300k miles or so. I've gotten into the habit of performing drain / fills every 30-40k miles. I'm about to hit 150k and plan to pay a shop to drop the pan and replace the internal filter along with whatever fluid replacement.


See above. Unless something changed in CX-5 design recently, it is NOT a sealed transmission.

Just to add additional context, more and more manufacturers are using this BS. Toyota and BMW do. The prior Toyota I had was a 2019 C-HR LE with a CVT. I contacted my dealer about getting the fluid changed. The first guy I spoke to said it's sealed and there is no need. I pushed back. Another service writer got on the phone and gave me a quote to do the service. I ended up going to an indie shop to have the trans flushed with a BG machine.

Same thing with BMW. I have a 2013 135i with a DCT. Wanted to get the fluid changed out. And this is the surprising thing. I talked to my friend that's been a long time BMW tech. He said the same thing about it being sealed and there being no need. I pushed back and asked him to do the service anyways.

With the C-HR on the C-HR forums, you'll see a ton of posts about transmission failures. None of them did any fluid services. I've gotten into arguments with these people about why routine fluid service is needed despite the "lifetime" claim. But they would rather cry about it, threaten Toyota with a lawsuits, etc, etc. Meanwhile my car had 185k miles on the original engine and trans until the car got totaled from being rear ended.

I'll be doing the same protocol with my 2025 CX-5 that I've done with my other cars.
 
I'll be doing the same protocol with my 2025 CX-5 that I've done with my other cars.
Yep, this is what got me to start doing it...albeit a little late at 71k miles for my first one, but that's when I started getting into DIY and taking a more active interest in learning this stuff.

Yeah what good is threatening to sue a manufacturer when your car is dead and done. Better to just take care of it properly. I don't care what anyone says, fluid will always be a wear item. Some holds up better than others. I think the Type FZ fluid the CX-5 uses (its blue) seems to be really good and haven't heard of many transmissions failing from the "I never changed it" crowd either I'll admit, but I think it's just logical that fluid is a wear item and an automatic transmission is an automatic transmission. If you know how those work, I think it's still prudent to maintain it properly with transmission fluid. I'll change the fluid periodically given it's my intention to own the car for many many years to come (April will mark 13 years so far).

As for cylinder deactivation...my nephew has a 2019 (I think...) CX-5 with cylinder deactivation and let me tell you he had an issue a few years ago where he had issues with the hydraulic lash adjusters causing issues with the rocker arms. I forget the details, but it was some issue the dealership ended up covering due to the cylinder deactivation and some TSB I believe. Personally I think cylinder deactivation is a terrible idea and CAFe is ruining cars.
 
Last edited:
Yep, this is what got me to start doing it...albeit a little late at 71k miles for my first one, but that's when I started getting into DIY and taking a more active interest in learning this stuff.

Yeah what good is threatening to sue a manufacturer when your car is dead and done. Better to just take care of it properly. I don't care what anyone says, fluid will always be a wear item. Some holds up better than others. I think the Type FZ fluid the CX-5 uses (its blue) seems to be really good and haven't heard of many transmissions failing from the "I never changed it" crowd either I'll admit, but I think it's just logical that fluid is a wear item and an automatic transmission is an automatic transmission. If you know how those work, I think it's still prudent to maintain it properly with transmission fluid. I'll change the fluid periodically given it's my intention to own the car for many many years to come (April will mark 13 years so far).

As for cylinder deactivation...my nephew has a 2019 (I think...) CX-5 with cylinder deactivation and let me tell you he had an issue a few years ago where he had issues with the hydraulic lash adjusters causing issues with the rocker arms. I forget the details, but it was some issue the dealership ended up covering due to the cylinder deactivation and some TSB I believe. Personally I think cylinder deactivation is a terrible idea and CAFe is ruining cars.
check the dipstick on transmission to get the correct fluid fz is one but a7 is newer -think its for c/d vehicles-they have it marked on the outside and inside the stick itself-its a challenge to find it....but it's there
 
check the dipstick on transmission to get the correct fluid fz is one but a7 is newer -think its for c/d vehicles-they have it marked on the outside and inside the stick itself-its a challenge to find it....but it's there
For C/D and i-stop. My 2025 uses it. Type : A7
 
Last edited:
check the dipstick on transmission to get the correct fluid fz is one but a7 is newer -think its for c/d vehicles-they have it marked on the outside and inside the stick itself-its a challenge to find it....but it's there
My mistake. I forget there are turbo models these days.
 
Back