Transmission running hot, part 2 and update - final verdict

Both usually, the tc was raising pan temps. The puck system provides no ability to cool, it's meant to bring tranny temps up 200 degrees quicker on cold start. Essentially boiling water is the only thing cooling an even hotter tranny.

 

Well put

 

I have heard the same thing on the Land Cruiser about the 305F Temp warning. But they also have some logic where if the engine coolant temp is 203F+ and the torque converter fluid temp is 265F+, it will lock the torque converter up to try and slow or stop the temperature climb.

Problem is, that logic probably only kicks in under heavy load towing because the coolant temps likely arn't getting up near 203F in normal circumstances. My LX570 was pulling Cajon pass out of San Bernadino at 70mph and the coolant was only 197F near the top.

 

It's no secret that Toyota cut corners, starting in the 2019 with the trans cooler. Same crap they fed the OP is the same crap they fed use previous gen owners. It was to line their pockets, period. It's been proven time and time again that a trans cooler is needed. Before my trans cooler install, I saw 220+++ driving around the Smokey Mountains. Now with the cooler never see 200. Glad I did it early on and especially now the I am SC'ed.

 

Instead of a useless $3k TRD tune that Toyota offered. I would have been happy with a plug n play transmission cooler…

 

I ran into this transmission temp issue on my first off road trip and it was what I would consider the bunny slopes. And I was in 2wd. Will try tow/haul next time around. I also tried manually staying in 2nd gear about 1800-2000rpm and it didn't make a difference. Alot of the uphill sections were only a few hundred yards long.

Talk about being frustrated. I felt like I needed to peel the TRD off road stickers off.

i snapped this pic at the top of a hill. Thanks @SDHNTR for keeping us updated with your findings.

 

Yes, it will happen in 2wd also, just gets there faster in 4wd. PLEASE do us all a favor and report this to your dealer. Make them open a case with Toyota. They have no idea this is a regular issue. This needs to be recorded! Not enough people use these trucks in this manner to be noticed so the dealers don’t see this often and have no idea what to do. Nor does Toyota, I’ve had a case open for over a month now with zero resolution and zero answers. They can’t even tell me where that gauge is reading trans temp from, nor what the actual temps are when the gauge is reading that high. It’s an embarrassment!

 

So did it overheat?

 

A gauge reading that high under no or low load IS overheating! What if he was towing a trailer?

 

Did it hit the red section at some point? Or just got close?

 

Mine will definitely hit the red if you let it. But common sense says to stop and let it cool down before it gets to that point.

 

It got close to the red but actually never went into the red. I would have stopped had it hit the red.

 

So no one monitored actual temps. Mine hit 245 during an offroad excursion.

 

I haven’t monitored actual temps. But I did my first real tow with my 2024 yesterday. I’m in Phoenix and I did some steep hill climbs yesterday on the Interstate to get out of town in about 95 degree weather. My trailer and cargo was roughly 3,500 lbs, well below max. Trans gauge was hitting about 75% of the way to the red, which concerned me with such a light trailer at 70-75 MPH.

More concerning, IMO, was oil temp got much closer to red during the climbs. I will definitely be adding a trans cooler to this truck. I could easily see overheating in hot summer temps while doing slow speed off-road climbing.

 

How do I get the trans temp to display on my hybrid?

 

I have the digital gauge cluster, and I have an option for towing gauges. If you don’t have the digital cluster, I’m not sure you have that option. It doesn’t show the actual temp, it’s just a digital bar gauge.

 

Seems high. Were you in 2Hi, 4Hi, or 4Lo? I’m guessing 4Hi for that temp…

 

I have digital cluster. The arrows on the steering wheel customize the left side of the cluster, haven’t found anything to change the display on the right side (has round gauges for turbo and hybrid motor)

 

it’s was 4Hi, traction control disabled. My truck has the JB4, was on Map 5…

took it a while to come back down. Like 30 minutes. Had to drive it on the highway to circulate some air in there.

 

Go to settings tab on the left side of the speedo, scroll down to "Customize Right Side", hold until the menu displays, then scroll down to "Tow Gauges", and hit Ok to select. The right side will switch over to 4 bar graph gauges for Boost, Hybrid Battery, Oil temp, and trans temp.

 

I tried switching to 4Lo to see if temps would go down. But it bogged down too much for the type of terrain I was trying to go over.

 

So does the engine temperature climb above normal too or just trans temp? Seems odd that trans has to be on highway where it can get more air so it can cool down. Makes me think you have cooling problems or lack of cooling. Not from being over worked and getting warm.

 

Average temps where 190 to 195 for engine coolant. So I don’t think cooling was any issue.

 

you can see in my pic that oil and coolant temps were normal, it was just the trans temp for me.

 

Thanks!

Is there already a thread on tips and tricks for using the technology on these trucks? If not I may start one.

 

Not meaning to continue the hijacking of thread; I vote for new thread on technology. I'm not a tech neophyte by any means, but I'm way behind the power curve in learning all the tricks with the tech on this truck. Granted, this is my first Toyota product since 1990 and every manufacturer has their own software interface approach; I'm still struggling to become familiar with it all so I can rely on "muscle memory" to do things quickly.

 

Again, please take into dealer to log this concern! This needs to be documented.

 

Exactly. Everyone has said 4Lo is the "solution". It's absolutely not. It only makes for miserable driving conditions. I shouldn't have to go through the hassle to shift into 4L to keep a trans from overheating when the terrain comes no where close to needing it.

 

I've never seen oil and water temps go past half on the gauge, it's only the trans.

 

FYI, for those following along with my issues, there was a part 3: https://www.tundras.com/threads/transmission-temps-the-saga-continues-and-more-questions.142143/

And here we are a month later and I still have no questions answers. These basic questions must be really hard for Toyota to find answers to. The dealership transmission tech know nothing. It's literally unbelievable to me.