Put a transmission cooler, thats the first thing I did to my FJ Cruiser and never regretted it. Transmission never goes over 175 on steep hills or stop and go traffic as earlier 200 to 210 was common. Best of all the shifts are far more smoother and I don't find my transmission holding to gears that was typical once the oil would touch 200 plus. I put a Hayden 679 routed after the radiator cooler.
2019 Tundra High ATF Temperature
- Thread starter Whalstib
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Originally Posted by RoyFJ
Put a transmission cooler, thats the first thing I did to my FJ Cruiser and never regretted it. Transmission never goes over 175 on steep hills or stop and go traffic as earlier 200 to 210 was common. Best of all the shifts are far more smoother and I don't find my transmission holding to gears that was typical once the oil would touch 200 plus. I put a Hayden 679 routed after the radiator cooler.
The latest Tundras don't have an oil takeoff to connect to a cooler (I have a 2019). The part can be bought for about $200 but its not a trivial installation. Dealer never said as much but indicated it could void warranty.
bc
Put a transmission cooler, thats the first thing I did to my FJ Cruiser and never regretted it. Transmission never goes over 175 on steep hills or stop and go traffic as earlier 200 to 210 was common. Best of all the shifts are far more smoother and I don't find my transmission holding to gears that was typical once the oil would touch 200 plus. I put a Hayden 679 routed after the radiator cooler.
The latest Tundras don't have an oil takeoff to connect to a cooler (I have a 2019). The part can be bought for about $200 but its not a trivial installation. Dealer never said as much but indicated it could void warranty.
bc
The Toyota dealer here told me the same, also its lifetime fluid that never changes dialog as well. However seeing how the temps were crossing 200 on regular basis while doing hills and stop and go I decided it was not worth living with tranny shudder after warranty was over. I did read up about the 2019 Tundra cooler and you are right its very complicated and at this stage the warranty issues makes it non advisable. What I suggest is monitor your transmission temps and do a regular drain and fill.
I have a 2014 tundra with the towing package and a factory "integrated" cooling circuit and thermostat mounted to the side of the trans. If you crawl under the truck, press on the external button on the thermostat, then place a paper clip or small gauge piece of wire in the slot to hold the button down, that transmission will never go above about 140 degrees.
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Look at the tsb out there about changing fluid in these transmissions, it tells you exactly what to do if you want to experiment
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Look at the tsb out there about changing fluid in these transmissions, it tells you exactly what to do if you want to experiment
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Originally Posted by naveydavey
I have a 2014 tundra with the towing package and a factory "integrated" cooling circuit and thermostat mounted to the side of the trans. If you crawl under the truck, press on the external button on the thermostat, then place a paper clip or small gauge piece of wire in the slot to hold the button down, that transmission will never go above about 140 degrees.
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Look at the tsb out there about changing fluid in these transmissions, it tells you exactly what to do if you want to experiment
The 019 models no longer have that feature. Last ones were 018s. No oil takeoff available.
bc
I have a 2014 tundra with the towing package and a factory "integrated" cooling circuit and thermostat mounted to the side of the trans. If you crawl under the truck, press on the external button on the thermostat, then place a paper clip or small gauge piece of wire in the slot to hold the button down, that transmission will never go above about 140 degrees.
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Look at the tsb out there about changing fluid in these transmissions, it tells you exactly what to do if you want to experiment
The 019 models no longer have that feature. Last ones were 018s. No oil takeoff available.
bc
Originally Posted by naveydavey
I have a 2014 tundra with the towing package and a factory "integrated" cooling circuit and thermostat mounted to the side of the trans. If you crawl under the truck, press on the external button on the thermostat, then place a paper clip or small gauge piece of wire in the slot to hold the button down, that transmission will never go above about 140 degrees.
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Interesting, thanks--I've always wondered what would happen, but never bothered to try.
I have a 2014 tundra with the towing package and a factory "integrated" cooling circuit and thermostat mounted to the side of the trans. If you crawl under the truck, press on the external button on the thermostat, then place a paper clip or small gauge piece of wire in the slot to hold the button down, that transmission will never go above about 140 degrees.
I did this once after doing a fluid change and forgetting to un-pin the thermostat after the fluid change.
Interesting, thanks--I've always wondered what would happen, but never bothered to try.
Additional comparison. My wife and I were window shopping at houses last weekend. It was all 1-2 gear for 45 minutes, all at 15 mph or less. F150 10spd trans stayed at 206-208F the whole time. Not the "room temperature" behavior of the past.
additional observation from this weekend - somewhat related. In our 2018 F150, if the driver manually selects either of the top two gears (9-10), the engine is output-limited to approximately 1/3 throttle, or even a little less. Shift down to 8th, and it is fully available. Manually in 9 or 10, you basically can step on to it as deeply as you want, but it basically stops right at the point where the turbos start to be needed.
These two gears are also locked out if Tow Mode is selected. So basically, for whatever engineering criteria the chevy/ford joint 10-spd was built to, the 2 OD gears are intentionally torque limited by design.
-m
These two gears are also locked out if Tow Mode is selected. So basically, for whatever engineering criteria the chevy/ford joint 10-spd was built to, the 2 OD gears are intentionally torque limited by design.
-m
http://www.f150hub.com/trans/10r80.html
If this is to be believed, top three gears are OD. 8th is 0.85:1.
If this is to be believed, top three gears are OD. 8th is 0.85:1.
Get a VOA of the fluid and take samples at 30K, 60K, 100K. As long the as the oxidation is under control don't worry about it.
Originally Posted by supton
http://www.f150hub.com/trans/10r80.html
If this is to be believed, top three gears are OD. 8th is 0.85:1.
Thanks for the link - good read. 3 OD ratios. Wow.
8th 0.85/1
9th 0.68/1
10th 0.63/1
9th and 10th are aggressive ODs.
http://www.f150hub.com/trans/10r80.html
If this is to be believed, top three gears are OD. 8th is 0.85:1.
Thanks for the link - good read. 3 OD ratios. Wow.
8th 0.85/1
9th 0.68/1
10th 0.63/1
9th and 10th are aggressive ODs.
So the top two ratios are total fuel economy ratios only. Strictly for stretching the legs under light load and higher speeds. Makes enough sense.
Originally Posted by Whalstib
Howdy,
Just bought a 2019 Tundra 5.7L 6 speed automatic with tow package, to tow an Airstream. Previously same Airstream with a Tacoma had ATF in the range of 150° to 190° (190° towing up 6% grade in 80° ambient with head wind).
Tundra is running 215° without towing... Fwy driving 65-75mph. Lost of "complaints" about this but consensus is Tundras run hotter for a variety of reasons BUT reading here and elsewhere the ATF itself will suffer with 220° being a caution zone.
It seems part of the issue is a lack of a true ATF cooler and uses a heat exchanger and Toyota more concerned with running cold than hot...
Fine Toyota designed a Tundra transmission that excels at 220°+ BUT can modern ATF actually handle prolonged temperatures without premature failure?
Guys on the Tundra forum are all over the map with ideas but nothing confirmed.
So... CAN ATF handle these extremes day and day out?
Thanks,
Whalstib
Given as the Tundra is, according to CR, the most reliable half ton in America by a long shot (seriously it's not even close), I wouldn't worry about it too much. The transmissions are not a major problem in these trucks.
Howdy,
Just bought a 2019 Tundra 5.7L 6 speed automatic with tow package, to tow an Airstream. Previously same Airstream with a Tacoma had ATF in the range of 150° to 190° (190° towing up 6% grade in 80° ambient with head wind).
Tundra is running 215° without towing... Fwy driving 65-75mph. Lost of "complaints" about this but consensus is Tundras run hotter for a variety of reasons BUT reading here and elsewhere the ATF itself will suffer with 220° being a caution zone.
It seems part of the issue is a lack of a true ATF cooler and uses a heat exchanger and Toyota more concerned with running cold than hot...
Fine Toyota designed a Tundra transmission that excels at 220°+ BUT can modern ATF actually handle prolonged temperatures without premature failure?
Guys on the Tundra forum are all over the map with ideas but nothing confirmed.
So... CAN ATF handle these extremes day and day out?
Thanks,
Whalstib
Given as the Tundra is, according to CR, the most reliable half ton in America by a long shot (seriously it's not even close), I wouldn't worry about it too much. The transmissions are not a major problem in these trucks.
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