I googled the proper procedure to check ATF fluid level and came up with various opinions. I know you need to warm up the fluid by driving it around but is it best to check with engine running or shortly after shutting it down?

 

From my manual, page 284, 2014 RDX:

Check the fluid level when the engine is at normal operating temperature.
1. Park on level ground, and start the engine.
2. Wait until the radiator fan starts and then turn off the engine.
[Perform step 3 after waiting for about 60 seconds (less than 90 seconds).]
3. Remove the dipstick (yellow loop) from the transmission and wipe it with a clean cloth.
4. Insert the dipstick all the way back into the transmission securely, as shown in the image.
5. Remove the dipstick and check the fluid level.
[It should be between the upper and lower marks in the HOT range.]
6. If the level is below the lower mark, add fluid into the dipstick hole to bring it to the level between the upper and lower marks, and have your vehicle checked by a dealer immediately.

Everything else is just opinion, and of course that includes opinions about whether to do what the manual says. In this case, I do what the manual says.


RFT!!!
Dave Kelsen
--
People will accept your ideas much more readily if you tell them that Benjamin Franklin said it first.

 

Thank you. I checked my 2016 manual and did not see this. Exactly what I needed!