Transmission Overheating - anyone else?

[RideWithYanu]

Just another report on the issue, nothing new:

Yesterday I experienced the transmission temp raise up to the point that it initiated a warning. I had been ripping through some remote dirt roads pretty hard, pretending I was back in my rally days. Around 5k ft, and all uphill (quite steep in most areas). 4-Hi, everything unlocked. Again, really going full beans on it. Once I reached the trail I was looking for I began the real climb, still in 4-Hi. Once I got the dash alert (I had noticed the transmission temp rising) I went ahead and shut the engine down and took the chance to walk the trail a ways to make sure it was going to be wide enough. I returned to the truck about ten mins later and the temp was back down to about 3/4 of the gauge (I can’t recall the actual temp). After that point I went down to 4-Lo and carried on with a close eye on the temps; they continued to drop down to normal temps, and didn’t rise again for the rest of the day.

 

[jarussell4]

Coming from the Jeep World...That is not normal in other vehicles. As the first person who reported on this thread said, even CRV's and Subarus can go up on drive and not have any issues. On the Jeeps, it has to get very steep for it to use 4lo, on the 4xe, you almost don't need 4lo ever.
I went all in on Toyota for its reliability and I do not feel so comfortable now, really starting to regret the change.On top of all I am only getting 16-17mpg on freeway and driving 70 and below.
Took it to the dealership today and the technician was surprised on both (the transmission going up on the temp and the mpg). They will do a full check and call Toyota. I am really hoping Toyota backs their vehicle as much as they talk about it. Will post an Update soon...

 

[RideWithYanu]

Coming from the Jeep World...That is not normal in other vehicles. As the first person who reported on this thread said, even CRV's and Subarus can go up on drive and not have any issues. On the Jeeps, it has to get very steep for it to use 4lo, on the 4xe, you almost don't need 4lo ever.
I went all in on Toyota for its reliability and I do not feel so comfortable now, really starting to regret the change.On top of all I am only getting 16-17mpg on freeway and driving 70 and below.
Took it to the dealership today and the technician was surprised on both (the transmission going up on the temp and the mpg). They will do a full check and call Toyota. I am really hoping Toyota backs their vehicle as much as they talk about it. Will post an Update soon...

They have a very, very long history of standing behind their vehicles. I suspect they will continue to do so.

 

[Bad1975]

I know that some of the folks that were towing with the new Tundra's were pinning the Thermostat open and it was helping, others were adding and external cooler. You can search more on www.tundras.com

Is it safe to pin open Transmission thermostat?

I might take you up on that thermostat. I honestly haven’t crawled underneath yet to look for the warming puck. I was mulling things over last night...

www.tundras.com

I wouldn’t recommend that, that is part of the fluid level adjust procedure that help the transmission reach operating temperature faster. Just like a radiator thermostat removed will cause an engine to overheat under load the same will occur with a pinned trans stat.

Either install a larger trans cooler or get a dedicated fan with thermostat for the OEM cooler.

I haven’t looked at 250s cooler but I’d bet it’s likely coolant and air cooled like most OEM coolers these days?

The coolant if using that type isn’t helping do much cooling especially if the rad fan is off and is more ideal for aiding to increase the fluid to operating temp quicker in cold climate/winter conditions and keeping the trans fluid in the AF coolant temp range when possible.

 

[jarussell4]

UPDATE:
Took it to the dealership yesterday 6/10 at 2:00 pm and Have not heard back as of today 6/11 at 4:30. I can see from the app notifications that they are opening and closing the front driver's door few times a day and the hood has remained open as well as the fron windows...so they are doing something. I will post more once they call me. I will not call yet as I want to give them time to run any type of tests they have to.

Will keep you posted