I'm confused now: 2EHA made a dig against the Tundra--of which I own one!--but have to begrudgingly admit that the dig has truth. But ollie thinks that I think that the OP's truck is kaput now... one does not follow the other.
2019 Tundra ATF.... Burned?
- Thread starter Whalstib
- Start date
Isn’t there a so called thermostat that you can pin to keep open? It may allow fluid to travel through the radiator. I know the Gen 3 Tacoma’s have one.
MolaKule
Staff member
Okay, I think the confusion here seems to be on the time line as stated.
Were the temperatures quoted above in bold AFTER the non-factory ATF cooler was installed or before?
MolaKule
Staff member
So it is known to oxidize super fast?
OK I messed up and was unable to edit the first post which should have said 260° was the highest I monitored.
Pre ATF cooler install I was getting ~230° on 75° days going 65 mph (~2500 max RPM) on flats to rolling hills)
AFTER adding the ATF cooler I am getting 180° on 100° day traveling up to 85mph on desert freeways....
Most who have installed this cooler kit are reporting similar 40°+ cooler ATF temps across the board. Although since I'm getting 50° cooler on hotter days.... I suppose the cooling effect of 85mph vs. 65mph to be considered...
OP-
For paranoia you come to the right forum. Chevrolet says the Dex six is good for at least 275 degrees before it breaks down. I am assuming that whatever Toyota uses it can tolerate that heat.
I have a thermostat in my transmission-it runs at 190 degrees regardless of ambient temperatures.
I think a 7,000 pound trailer-personally is a little to much for a half-ton, even a Toyota. But that's just me.
For paranoia you come to the right forum. Chevrolet says the Dex six is good for at least 275 degrees before it breaks down. I am assuming that whatever Toyota uses it can tolerate that heat.
I have a thermostat in my transmission-it runs at 190 degrees regardless of ambient temperatures.
I think a 7,000 pound trailer-personally is a little to much for a half-ton, even a Toyota. But that's just me.
Toyota has always rated conservatively and says 10,000 lb towing capacity with 5.7L ..... I was more concerned with other models like Fords that states 13,000 lbs towing with a 3.5L! So I'm actually pulling about half of what a Ford 1/2 ton says IT can tow!
BTW it has NO PROBLEMS towing! It has power to spare. I tow an Airstream as well which tows much below it's rated weight when drag figured.
perhaps a bit harsh. Ford also went away from auxiliary radiators and now does the same thing with an ATF-to-coolant heat exchanger. Can’t even add an external unit in those, as the heat exchanger bolts directly to the transmission. GM shares the same transmission. I imagine there are others too. Toyota is also not the only mfr with radiator-caused pink milkshakes, more common than I’d like to think.
I’d wager a bet that the thermostatically-controlled cooling valve on the transmission manufactured by Aisin in your truck is sticking. If you can’t diagnose it, take it in. Granted it’s a different gen, but we had a gen 1 tundra and at 150,000 it still towed solid, ran solid, never missed a beat, and was impeccably reliable. Take care of yours and I’d hope it would be good to you.
as far as the overtemps, I’d likely change the fluid. theres not a lot of love for WS but otoh, Toyota transmissions running WS often outlast the rest of the vehicle. It does change color quickly. My personal goto for WS is amsoil low vis ATF.
good luck.
m
How did you come to this conclusion? My temps, pre ATF cooler install, were typical of the 2019+ Tundras so they'd all have to be sticking.
It's running great! I suppose when I reflect it's the smoothest auto transmission I've ever driven (Aside from a 1969 Turbo-Hydromatic in my Chevy Van!)
Thanks!
W
UOA people did would say that it is still serviceable. I am not big fan of it, but just observation from UOA I saw and claims that it gets dark super fast.
Yes, maybe UOA, but I would do different ATF too.
I just can't wrap my mind that Tundra does not come with transmission fluid cooler.
It does have a cooler "Heat Exchanger" of some kind, I think people mean an "Auxiliary" Transmission Cooler.
Yeah, that what I am referring, auxiliary cooler.
I am not truck lover, but I would think considering what their intended use is that it would have more robust set up.
Most of the people that buy Tacomas and even Tundras never tow anything, use them to commute to work.
And chances are anyone that tows seriously will add an auxiliary cooler on their dime.
So probably a accountant determined that saving money on a air cooler for all their cars is more money than the few warranty calls for burned transmissions.
Now, the heat exchanger is still technically a "cooler". It just cools the transmission with a fluid at 185-190F. So obviously, that's the lowest the input fluid can go, so the transmission will have internal temperatures higher than that.
But 260F (like the OP corrected) is killing the seals, clutches inside transmission. As for the fluid itself, a synthetic fluid might be OK, but Toyota WS is not that.
And chances are anyone that tows seriously will add an auxiliary cooler on their dime.
So probably a accountant determined that saving money on a air cooler for all their cars is more money than the few warranty calls for burned transmissions.
Now, the heat exchanger is still technically a "cooler". It just cools the transmission with a fluid at 185-190F. So obviously, that's the lowest the input fluid can go, so the transmission will have internal temperatures higher than that.
But 260F (like the OP corrected) is killing the seals, clutches inside transmission. As for the fluid itself, a synthetic fluid might be OK, but Toyota WS is not that.
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Most of the people including me that have a Tundra use it for towing. You also have a load in the cabin and bed of the truck. I know all my trucks get significant use. It appears that Toyota did something different that will probably cost them later for these specific year trucks. Mistakes happen.
Toyota WS is made by Mobil. I use Valvoline Maxlife and do a drain and refill when it needs it. Both my 2008 Tundra and my 2014 Tacoma come with a complimentary Lifetime Powertrain Warranty. That warranty certificate is good till 999,999 miles.
Toyota WS is made by Mobil. I use Valvoline Maxlife and do a drain and refill when it needs it. Both my 2008 Tundra and my 2014 Tacoma come with a complimentary Lifetime Powertrain Warranty. That warranty certificate is good till 999,999 miles.