Should I be concerned about these transmission temps without towing?

I have a 2021 Tundra. And temps got way high (imo) without towing. What are your thoughts?

 

I'd call that high.

 

They took the trans cooler off in 2018. I installed an aftermarket cooler kit from genuine cooling system .com and it hasn’t passed 200 even with heavy towing in 100° weather. Highly recommend. Hardest part of installation is running the OEM hard lines that come with the kit

 

I have put myself on the wait list. It is now like 1300 bucks. But I would assume it will be worth it.

 

He has had various kits over the last few years but they are legit and high quality kits. @Genuine Cooling Systems is great to deal with.

 

I just sent a sample on ATF to Blackstone Labs. I have a 21 and tow. The temps you are seeing for the TC are normal. Sitting at a stop light or climbing a small hill will bring the TC temps up real quick but they drop back down just as quick. I don't like your pan temps. Is that normal? Seems like your WT is higher that mine. 194 is about normal for me.

 

With the the cooler kit mentioned I rarely see temps over 200. Temps drop fairly rapidly.

 

I see temps around 230 pan when towing my 8000# travel trailer. What’s the details on this drive you were going? Emergency brake on the whole time?

 

2018 has it. 2019 is when it was removed.

 

2018 has the trans cooler and the new Yf1234 or whatever refrigerant that’s less effective. AC performance suffered. They removed it in 2019 to help with AC performance. Unclear on whether they increased the condenser size.

 

That temp is still in the acceptable range according to Toyota. The warning light goes on at 300 degrees.

With that said, I tow a fairly large travel trailer with my 2018 and I will only see that range if I run with a heavy load and use 6th gear going up a hill and the torque converter isn't locked. The highest I have seen even with the factory cooler is 257 degrees.

In S4, which is where I sit most of the time, the torque converter is locked and the temps balance between the pan and converter at a lower range. Next time you see those drop it into S4 and watch it drop.

 

My pan temps have never gone over 230° when towing. I always tow in S4. Torque converter temps will get up around 250° during uphill pulls, but will quickly return to pan temps when leveling out. No trans cooler.

 

Is that the reason for the removal? AC performance over towing cooling? I don't think I have ever learned about an actual "Why" except people complaining about Toyota cheaping out.

 

That’s the explanation that was given. I imagine it was “everyone uses the AC. Only some people tow”. Plus they say the WS Toyota trans fluid is stable at higher temperatures. We have not seen a rash of failures related to the removal of the trans cooler.

 

It's a logical answer and I appreciate the info. And yes, I haven't heard of any transmission failures directly related to overheating in the 2019+. Most people just hitch up and go while never giving it another thought.

 

I think most people would be surprised to hear that Ford also removed the transmission cooler from the F150 in 2021.

 

I think it was removed to save a few hundred in manufacturing costs. Resulting in a situation where the transmission survives in the most common use cases but outlier activities (like actually towing etc) can lead to long term problems that weren’t present in prior model years.

 

Ha, wrong thread. Ignore my previous jibberish. Meant to say, I was pulling a small enclosed trailer yesterday for a couple of hours through hilly terrain around 65 or 70 MPH. Pan temp right at the end of the the trip was 208 degrees before I throttled down.