Typical transmission temps?

Not conclusively so. I say that because I feel like I get something different every time I tow. I got about 10 mpg on the way there and about 9 on the way back. My best ever while towing was about 11 mpg (tail wind, no doubt) and my worst is about 8 or 8.5 mpg. So I'd say my mileage on this trip was typical and not outside of my norms.

 

I can't say that I've really done enough towing in D to come to a conclusion. The instantaneous and average figures from the scan gauge were as usual. One thing I can say is the stock '21 sure heats the fluid when towing in drive.

 

I bought a used 2020 tundra with 47,000 miles. The previous owner towed with it, I owned it for 2 weeks and the transmission went out. Toyota replaced it under the powertrain warranty. These things do fail if they aren’t taken care of properly. I’ll definitely be changing the fluid every 40-60 thousand miles or whatever the book says. I guess it’s more of a refresh than a change since you are only getting about 4qts in and out.

 

Toyota service manual doesn’t talk about changing the fluid.

 

Actually it does if you read it…..

 

fair. I forgot about the special operating conditions. It’s not in the normal vehicles operations portion.

the dealer tries to tell me every visit I need every special operations service. My tundra has towed two trailers in its 52k life so I guess that makes it special operating conditions.

toyota intended for the majority of these transmissions to go their entire lives without having fluid changed. Ford does the same thing. I had a 2014 f150 before this tundra and the manual never called for a fluid change under normal conditions.

 

Just another datapoint : I have the 2020 with engine / transmission / cat skidplate I live in Vegas and I got up to 240 towing (3500lbs tall trailer) in 110F and 224F in S4 ( about 65 mph). two weeks later on same stretch of freeway I was around 220F without the trailer in 102F weather (about 70-75mph).
once weather cools down a bit I will drain the transmission fluid at about 57,000miles.

 

I bit the bullet and installed a transmission cooler. Much better on the temps now. Attached is a photo after the cooler. The same trip on the way to install it I was getting 210 degrees with converter spiking as high as 230 it was 85 degrees outside. After the cooler install the converter has yet to spike above 210 and usually stays well below 200 degrees.

 

Pinned thermostat and cooler installed. Here are the transmission temps in 100+ degree weather in the southwest.

Top pic was after stop and go traffic, 2nd is cruising on the freeway.

Without the transmission cooler, I've seen temps as high as 240 deg.

 

Well it has been over 5 years since the 2019 Tundras came out without the air to fluid transmission cooler. A lot of debate at the time of whether the higher operating transmission temps would cause any transmission failures. There should by now be some fairly high mileage Tundras without the coolers out there. Any reports with failures? Any high mileage ones out there that have survived without the cooler someone wants to brag about?

 

You’ve also got the Sequoias that went this same direction that have to be getting some miles. Unless you are towing very heavy most people don’t need one

 

@WiscoWalleye reported the failure of a 2020 transmission, post #218 just above.
Here are a few others I found. Worth reading these threads if interested:

 

What determines if a truck gets a cooler from the factory? I thought it was only the 2019+ that did not get them, but my 2015 doesn't have a cooler.

 

Does your truck have the tow package?, that could be the reason.

 

It has a tow hitch and trailer plug. That's not the tow package?

 

I would think so if its factory, there's no auxiliary cooler in the front behind your grille?

 

No, only the power steering cooler on the bottom.

 

Very strange, did you buy it new?

 

No, i just got it. That's why I thought it was strange. I also had a 2013 before, with tow hitch and trailer wiring. No trans cooler either.

 

I always thought if you had the tow package you got the cooler, but I guess I'm wrong. Maybe others here with a similar truck to yours can chime in and clear this up.

 

I dont think 5 years is nearly enough time to tell. I have a 2019 and only have

Look under your truck at the transmission and see if you have lines running to the front The cooler is part of the AC condenser and not a separate radiator.

 

Yes mine failed at 45,500 miles. Previous owner towed a heavy ice castle with it in the winter and job trailers. Nothing that the truck shouldn’t be able to tow on a regular basis. My transmission was fully replaced under warranty fluid was all burnt and contaminated. Anyone that uses their truck as a truck not a city boy waste of space look at me bro machine will risk blowing their transmission without a cooler.

 

Oh i was looking for something like this. Aren't the lines from the transmission running to the radiator? That's how my tacoma is, so I assumed this was the same. I never actually followed the lines. I will check next time I get under.

 

Someone correct me if I'm wrong, but the 2/2.5 Gen Tundra has had multiple iterations of the cooler.

1) separate standalone unit (similar to photo directly above only from the factory) 2008-2013?
2) integrated into the radiator 2014(?)-2018
3) none existent and people are adding an aftermarket external back to it (see photo directly above for an example of a GCS version). 2019-2021

Just because you don't see it may not mean you don't have it in #2.

 

4.6?

 

Correct The cooler before 2014 was a standalone radiator after 2014 it was integrated into the AC condenser and then in 2019 it was eliminated.

 

You're mostly correct except for #2 - it was was actually Integrated into the AC condenser not the radiator.

And technically for #3 they had an "integrated cooler" whereby the ATF is cooled/warmed (depending on who you ask) by the engine coolant in a small puck like unit right beside the transmission.

 

That puck actually always existed in the previous models that came with a cooler as well which is why most refer to it as to warmer since it's largest function is too warm the fluid on a cold day using the warm fluid from the radiator. Does provide a small cooling factor when the ATF fluid is hotter than the coolant but it's so small that it doesn't make a big enough difference when the ATF gets very hot. If you look at my read out here in this type of situation the coolant is actually still going to raise the temperature of the transmission fluid because my coolant temperature is higher whereas with an external radiator the outside air temperature will always be cooler than the fluid temperature going to the radiator after the thermostat opens.

 

We’re all friends.

 

I regularly see temps in the 250s in texas, not towing, just driving.

I think im gonna get a cooler installed here soon.... Toyota says temps are not an issue until 300? I think. Not sure how much I trust that. I did get my transmission fluid changed at 50K