Guide: 2016~2021 CX-9 DIY Transmission Fluid Drain and Fill + Filter Change

Here's a very useful tool to separate oil pan from aluminum tranny housing;

Oil Pan Separator Tool


Once the pan was removed, use this solvent, use plastic blade after 10 minutes or so;

Silicone Gasket Remover, Motorcraft ZC-30-A
The trans oil pan was like $26 before shipping with no tax at partsouq.com so not much savings vs silcone dissolver at $19. Hopefully I wont need the separator at around 60k mi lol
 
The trans oil pan was like $26 before shipping with no tax at partsouq.com so not much savings vs silcone dissolver at $19. Hopefully I wont need the separator at around 60k mi lol
You'll have to separate the pan from aluminum and still need to clean up the RTV residue on mating surface without much scratch as possible..
 
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There's your answer, right there! The MK808 absolutely reads trans temps!

1643067347728.png
 
There's your answer, right there! The MK808 absolutely reads trans temps!

View attachment 306788
Oh wow nice.

Btw my Civic just had a check engine light on right after I installed the transmission mount. All I removed was the air cleaner box and unplugged the mass air flow sensor, loosen the ecu bracket and wiggled the ecu around along with the fuse box. I did not inplug the ecu nor the fuse box just wiggled it a few times. I guess I can bring it in to Orielkys somce they have free check engine light obd ii scanning. Has anyone tried Oriellys?
 
Btw how long did it take to read 122 deg? Also whats your location and time of reading?
The car was key on engine off when I did the reading, and it hadn't been cranked for about an hour and a half. I didn't monitor it to see how long it took to hit 122, I just was checking to see if the PID was able to be read.
 
Btw how long did it take to read 122 deg? Also whats your location and time of reading?
If you're considering the idea of deriving tranny fluid temp by using the observations of others (or by any other 'estimation' method for that matter), I urge you to not do that. You need to be aware that TFT is very much affected by ambient temp and length of vehicle down time.

So the length of time for the fluid to reach the target temp can differ quite a bit, depending on the two variables above. And that's true even when just comparing multiple warm-ups of your own vehicle, if ambient temp and/or down time is quite a bit different each time.

So if you want to do this job right, and not potentially damage your transmission, then get one of the tools which correctly reads the TFT pid on your vehicle. If I didn't already have something, I'd take a look at FORScan Lite, which yrwei52 and others have mentioned previously. The acid test of a valid reading is for the TFT values to be quite a bit lower than ECT, during a warm-up of a completely cold vehicle. And TFT will not catch up to ECT for a long time either - perhaps as long as 20-25 minutes.
 
The actual coolant temperature indicator light deactivation on cold engine start up if you independently test and check is 129.9F. You can't go by the OBDII in this case because of scaling on reporting in the original programing form the ECU.
The temperature of the transmission is directly related and monitored about the same as the coolant. A better way to read the temperature is in the pan. That temperature is what will be run back through the transmission after any cooling effect by supporting fluid coolers.
It's my opinion that most all and MAZDA automatic transmission run on the hotter side for my comfort. I personally run an aftermarket cooler and even in extreme temperatures of summer seldom does my ATX temp raise above 180F measured with a analog gauge with the sender mounted in the stock oil pan. The coolant will get to about 205F-210F running the AC on max. with ambientes in the 100F plus temperature's. I will be addressing that this year. A BIG ARSE COOLER! I found that best performance and mpg is when the engine is at 185F coolant IATs at least the ambientes and the transmission at or below 180F . A transmission can heat up the engine coolant if it is not controlled efficiently and vise versa.
The fluid level in most Mazda transmission pans can safely support safe transmission operations as long as the fluid dip stick is at least at the mid point. I believe that a sustain 40 degree angle even if indicating at the 1/2 full mark on the dip stick would still pick up fluid from the sump? That is an "best guess" based on measuring the pans capacity and where the fluid picks up in the pan.
 
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Thanks for the write up, I hope you don't mind me adding some screen grabs to this instructional again. The more we have the better for those who will follow along.

I grabbed a screenshot of the dipstick location and drain bolt location:
View attachment 226675
View attachment 226676

Once replaced run the vehicle until the ATF fluid is 122' F (50'C). remove the dipstick with the engine idling on a flat surface and verify the level is within the range on the dipstick as shown below:
View attachment 226677
Once in the marker range reinstall and tighten the bolt to 71-97 in/lbs (8-11Nm)
Where did you get this service info from? Does it apply to 21 cx-5 GTR turbo as well?
 
Holy moly, that Autel is a steal! I just ordered one, thanks! I have a Foxwell now, and it's good, but it's not touch screen, and can only track one PID at a time. After I get used to the Autel, I'll sell that one.
Btw the mk808 only comes wiht 1 year updates but what exactly gets updated?
 
Sorry to hijack this thread a bit from the CX-9 crowd but I read a few posts in this thread that the 2.5T (GTR and Signature) CX-5 fill and level bolt placement is a huge PITA. I had a spare minute today and I wanted to take a second look for a small bolt I lost yesterday so I decided to investigate (RIP bolty mcbolt, you're gone but not forgotten you POS).

The fill/level inlet imho is not in an awful spot. You still need to remove the airbox and they recommend removing another metal bracket, but you don't really need to remove the metal bracket. You can access it just fine from the front or partially from the side. I removed the level bolt from the front pretty easily and it would be very easy to get a flexible funnel in this inlet.

As for measuring the temperature. I found my bluetooth OBD scanner got the job done with OBD Fusion and the upgraded sensor reading package from OBD Fusion. All in it was like $20 for the bluetooth OBD scanner, $5 for the app and $15 for the upgrade package to support more sensors. It was able to read the ECT temperature just fine. I've attached a few pictures.

Picture 1 is looking at from the air box, the view is partially obstructed by the black tube next to that main electrical connector. You can remove that bracket to gain better access. There's two bolts, the one on the top is easy, the side one is a PITA, would not recommend.

Picture 2 is looking at it from the front of the car. The two black hoses on the left are very flexible and rubber.

Picture 3 is the gauge in OBD Fusion. The car had been on a while as I figured out all the app settings I needed.
 

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Sorry to hijack this thread a bit from the CX-9 crowd but I read a few posts in this thread that the 2.5T (GTR and Signature) CX-5 fill and level bolt placement is a huge PITA. I had a spare minute today and I wanted to take a second look for a small bolt I lost yesterday so I decided to investigate (RIP bolty mcbolt, you're gone but not forgotten you POS).

The fill/level inlet imho is not in an awful spot. You still need to remove the airbox and they recommend removing another metal bracket, but you don't really need to remove the metal bracket. You can access it just fine from the front or partially from the side. I removed the level bolt from the front pretty easily and it would be very easy to get a flexible funnel in this inlet.

As for measuring the temperature. I found my bluetooth OBD scanner got the job done with OBD Fusion and the upgraded sensor reading package from OBD Fusion. All in it was like $20 for the bluetooth OBD scanner, $5 for the app and $15 for the upgrade package to support more sensors. It was able to read the ECT temperature just fine. I've attached a few pictures.

Picture 1 is looking at from the air box, the view is partially obstructed by the black tub next to that main electrical connector. You can remove that bracket to gain better access. There's two bolts, the one on the top is easy, the side one is a PITA, would not recommend.

Picture 2 is looking at it from the front of the car. The two black hoses on the left are very flexible and rubber.

Picture 3 is the gauge in OBD Fusion. The car had been on a while as I figured out all the app settings I needed.
Thanks for posting your experience on checking the ATF level for a 2.5T. Can you tell us which bluetooth OBD scanner you’re using (or posting a link)?
 
Thanks for the write up, I hope you don't mind me adding some screen grabs to this instructional again. The more we have the better for those who will follow along.

I grabbed a screenshot of the dipstick location and drain bolt location:
View attachment 226675
View attachment 226676

Once replaced run the vehicle until the ATF fluid is 122' F (50'C). remove the dipstick with the engine idling on a flat surface and verify the level is within the range on the dipstick as shown below:
View attachment 226677
Once in the marker range reinstall and tighten the bolt to 71-97 in/lbs (8-11Nm)
“run the engine until the ATF temperature is 50 °C (122 °F),” also means that it is ok to read level at a little higher than 122F ?

Lets say when it is 122F then you pull out to check and insert it back in and pull out again so the atf temperature should be rising so the 2nd or 3rd read is higher than 122F?
 
“run the engine until the ATF temperature is 50 °C (122 °F),” also means that it is ok to read level at a little higher than 122F ?

Lets say when it is 122F then you pull out to check and insert it back in and pull out again so the atf temperature should be rising so the 2nd or 3rd read is higher than 122F?
Yes, very likely that’d happen. But the increase of the ATF level should be insignificant with the ATF temperature rises a couple of degrees above the 122°F
 
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