CCN says to pin cooler bypass open to ensure correct fill on the 8 speed UA80E trans. I have this on my 2020 ES. Does anyone know where the bypass is? Can you see/access it when you remove bottom cover panels? Thanks.

 

I got a 2 day subscription to TIS and looked at the Repair Manual. The ATF cooler is located under the battery. But, I see no reference to the thermostatically controlled bypass the Car Care Nut mentions in his video. ATF inlet and outlet hoses run directly between transmission body and cooler. So, it the thermo bypass exists, it is internal. I also looked at the transmission system itself and found no reference to the bypass.

So, maybe some UA80E tranny’s have it and some don’t.

 

I found this UA80F which might help. Slightly different transmission.
Post #11 has a video.

 

Thanks, I watched that too before I bought my subscription. RM shows a different style cooler for my car.

In order to access RM, I have to enter production date. They only give two options in the drop down menu. Neither applies to my car which was made 8/2020. Option closest to mine ends with 1/2020. So, maybe only way to tell for sure is to remove battery.

 

The depicted part 32970-34030 does not fit any vehicle with a UA80E/F transmission. But, the later model UA80E/F has what the RM calls a water bypass hose assembly. It looks like it is electrically controlled. Looks like only UB80E/F trans (low torque) have the thermostatic bypass 32970-34030.

The 8 speed appears to have many permutations. The RM does not say anything about the thermostatic bypass as it relates to setting ATF level.

 

In The Car Care Nut's "How to change your Toyota Sealed Transmission Fluid" video's description, he states:
The part I've bolded, I think, makes clear only some of the "new" 8 speed transmissions (e.g., UA80E) have an oil cooler bypass.

 

Could be wrong but I think 32970-34030 is only for trucks or the LX aka Land Cruiser.

 

Thanks, I never thought to read the description, crap! That clears up my confusion.

 

Ok, I looked at the RM for 2017-2020 Sienna. It shows the ATF (transmission oil) cooler thermostat. But, the ATF replacement procedure does not mention it. So, it looks like CCN’s video is asking for a refinement not called for by Toyota. Not unusual since he often calls for more stringent service than Toyota, eg calling for ATF replacement at 6 years regardless of mileage.