ATF fluid check temp monitor mode

Hi - working on a 2023 Capstone w/ 54K. I'm getting some fluid next weekend and would like to change the ATF myself. However, curious if the ATF fluid temp monitor mode is the same on the new gen Tundras as the last (jumper #4 and #13 pins of OBD port, shift between N and D rapidly to enable ATF temp monitor mode).

Anyone know if it's the same procedure? If so, hopefully it will keep the engine running on the hybrid system.

Also, does anyone know if there is a transmission fluid thermostat that has to be pinned open as well?

I'm not going to use a heat temp gun because that's pretty inaccurate. Plus, I don't know what the specified temp range is anyhow.

Thanks

 

Do yourself a favor. With the engine cold, drain what's in the pan and refill the same amount. Consider yourself done for another 20-30k miles.

 

Store your new ATF in the truck overnite so its the exact same temp/density as that in the tranny when you do the change.

 

^^^ that is the way the pre gen3 owers do it! Works fine! And as @demfer says just drain and fill cold = measure what you take out and put back the same. Repeat every week for two more weeks and call it good for another 30k.

 

My system is to do one exchange around 30k miles and then by 50k miles I’ll do it every other oil change or so which is 5k miles for all my trucks. Cheap insurance and I’ve kept trucks way beyond 400k miles doing this.

be sure to post photos of the work when you get to it, might be a good reference for members depending on how much of the tranny configuration has changed since the previous gen.

 

I can say this method worked on my 15 Tacoma. I measured what came out cold. The fluid I put back in was the exact temperature it needed to be. I did it during the summer. My pan temp reading was 97 degrees. I started it up and pulled the check plug and drained out till it trickled.

 

so then you,didn’t,just drain and fill?

 

I do this for my wife’s rav (and my tundra when it’s due). I never understood why the “get it up to temp and check the level”.

drain 2 quarts, then add 2 quarts. (New fluid at same temp as vehicle)

“But what if it was filled incorrectly at the factory???” Hmmm if I drove for 50k miles when I did this and it drove fine, then just drain and fill

 

To answer one of your original questions, Yes, it has a thermostat on the side exact same as the 3rd Gen Tacoma that needs to be pinned if doing the change by the book using temperature. I have not read or heard from anyone if the OBD bypass mode works on this truck. I kinda doubt it just because much of the OBD PIDs are different from any previous truck. (whole new ECU)

 

Check to see if you have wires in those to places. My 2021 did not. I used my Scangauge to read pan temps but did find it's a very narrow window of time after your idle finally settles down and your pan temps increase out of range. The ability to use the jumper trick brings your idle down right away.

 

Drain and fill

 

If you trust the oem fill to be correct then the drain and fill is fine. If you don't trust the oem fill then you need to have a level check done. I did not trust the oem on my Tacoma - had the dealer check it at first service and they said it was 1/2 qt low. I checked it afterwards and found their work was good. From then on I just did the drain and fill. Unfortunately, I'm not sure I would trust the dealer anymore based on what I see and hear. I'm going to make the leap of faith and say it came correct from the factory - it drives and shifts perfect even when towing. I'll be doing the drain and fill, but possibly once the level check procedure is verified for the Gen3 I may give it a try.

 

but you said you checked pan temperature, and drain valve until trickle?? That’s beyond a simple drain and fill, and essentially is the full procedure?

 

this is also my logic. I like to change out tranny, transfer, and differential fluids @50k. If I’ve been driving that long with zero shifting issues, I assume it’s the correct fill from the factory. Drain and fill = just fine.

 

I've always disconnected a trans cooler line, fired up the engine via remote start and pumped half to full gallon out and then added the same back in....do that with like 11-12 qts and then let it warm up and follow oem level check process.

 

Question, when doing the drain and fill, are you not changing the filter also?

 

Common misconception is that there is a filter element in the transmission pan area. It’s simply a mesh, there is absolutely no reason to disassemble the bolts holding the pan and changing that mesh. Is such absolute overkill and risks gasket misalignment, leaks or stripped bolts.

 

nope

 

This is called a "drain and fill, among other things"