2024 Transmission getting HOT in 4x4 climbing hills, skidplates?

Continue to argue, plz.

I'm finding value there.

 

Got it. Never had a ford and my GMs were older than ‘19…a decade and over, so makes sense. Haven’t paid attention to GM in a long time.

 

Ford and GM never have an transmission overheating issue, I use the 4 hi all the time when off roading on both the Ford and Tahoe as well as all wheel drive, they have never once overheated the transmission…. It’s just Yota…

I use 4hi with the traction control completely disabled.

 

You want the truth? Can you handle it?
Go up to your Front Diff and have a Come to Jesus Mtg with it.
Look at its round face. Stare it down and ask it nicely.....

Hey Diffy……if we are travelling on a good dry road, and I reach over to that thingy, button, dial thing on the dash and turn it so it points to 4Auto. Are you at this point going to be helping me drive the vehicle or are you just hitchhiking?
It will give you the truth.
'8^0

 

GM transfer cases are notorious for taking a shit.

 

why is this still going, seems like plenty of good options and other options have been provided but yet 7 pages of back and forth lol

1) use 4 LO
2) drive faster in 4 hi
3) use 2wd until you actually need 4wd, then 4lo or 4hi for a shorter distance
4) add another cooler to the truck
4) sell the truck and buy a ram, gm, or ford

 

because it is a public chat forum, its raining, and I don't want to do my taxes.

 

fair

 

Maybe not the transmission, but I've been in an Ecoboost truck that had the engine overheat.

 

My 2018 f150 hit 250 degrees in 2wd going 65!
Ford reflashed the control module and I really
fix the problem by purchasing a tundra.

 

Mine is 2736 at 62.3k miles.

 

UPDATE:

Had the truck into the dealer today. And go figure, they claim they experienced the exact opposite condition. They said they got the tranny "really warm" and it DID NOT register on the gauge as being warmer than normal. So after conferring with "Toyota engineering" they think that the sending unit/software communication from tranny to gauge is bad. I'm HIGHLY skeptical. They say they need to hook the truck up to the computer, drive it around, get it hot again, and video everything to send to Toyota Engineering on Monday. Gonna let them do their thing and keep my fingers crossed, but I almost want to laugh.

Oh and they are working on the excessive wind noise too.

 

A faulty sending unit or gauge was one of my first thoughts. I hope that's all it is.

 

You said you were done. No take-backsies!

 

We have emailed back and forth a few times, and I see 200 posts ago you suggested drilling extra holes for better flow in your Talons transmission skid, and I do not think that would change your situation in this case.

While we have not tried this on a Tundra, when we got our bronco and stared wheeling it V1 of our skids did not have any holes in it for airflow. I mostly wanted to test a theory and we took it wheeling the following weekend. We did not notice any change in transmission temps from stock as read on the factory digital gauge. We also hit some areas with a temp gun and had the same results.

While I do not doubt that the transmission skids hamper air flow to some extent, they do not totally block it, and it is not an airtight seal around the transmission area. There are lots of gaps all around the skids, along with our logo and vent holes to facilitate extra air flow. Think about trying to heat or cool your Tundra then rolling a window down. Even though there is a lot of cab around you, it really negates the ability to keep it hot/cold.

It sounds like you have the transmission skid off, and the dealer was able to get the transmission hot without it? Does this mean I can stop laying awake wondering about this now

 

Yes, you can. And I apologize if there was any insinuation it was a skidplate problem. It's not your problem, it's Toyota's. Or, well, I guess it's my problem more accurately as Toyota certainly isn't owning it. And here I am with an expensive, fancy truck that won't meet my needs the way I want it to.

Bottom line according to Toyota... Apparently everything is "normal". Picking my truck back up today after several days at the dealer. They said they were able to get the trans hot, but with computer hooked up and communicating to the Toyota engineering team, they deemed the temperatures hotter than normal, but not alarming. The dealership also took two other Tundras off the lot and were able to duplicate the exact same conditions I experienced. Lame. Guess, they weren't expecting anyone to actually hit the 4x4 button.

I miss the old Toyota. When the focus was put into building durable and reliable trucks rather than stupid bells and whistles. I really regret selling my 2017 4Runner.

 

If it makes you feel any better, your 4Runner was running too hot, too, under the same conditions. I had a 2012 4Runner before buying my Tundra, and I had issues where the torque converter started slipping (feels like you're driving on a mild rumble strip as it attempts to shift and hold the next gear). I thought that because it had a tow hitch receiver, it must have an appropriate tow package that includes a proper transmission cooler to keep transmission temps from running away when towing or in low-speed off-roading situations. Nope! And I did plenty of low-speed off-roading. Temp warning light is set way too high (it's like 302ºF on the 2nd gen Tundras ) so you and I probably never knew that we were north of 250ºF at the torque converter. Can't do that for too terribly long before seeing issues.

I do agree that we're seeing the end of an era with Toyota. The inefficient yet bulletproof, go anywhere and come back every time vehicles of the previous generations just got a LOT more complicated (and expensive). I'm sure that relative to the competition, their time-tested methods and philosophies will make them more reliable, but whether they'll be as reliable as the previous models has yet to be seen.

Carry on. (in 4Lo)

 

I've towed Fords, Rams and know that the transmission if the oil is too hot will require you to pull over and let it cool down. Also, the latest ATFs are far more temperature capable than fluids of just a few years ago. The Engine coolant and ATF temps will exchange heat as necessary.
The video posted in this thread show temperatures common with other manufacturers.

 

@OP, Please report the investigation you plan when returning to your mountain trails with the skid plate removed. I am interested to read the results. Thanks for bringing this issue forward.

 

If you want to keep and enjoy driving the truck in the same manner, add an external oil to air heat exchanger for the transmission.

This is not Toyota’s first screw up with transmission cooling in a Tundra. Early Gen 2 trucks have high load low speed issues.

As for skid plates blocking air flow, they certainly can, do, and may cause high temps and/or over heating of various components. How much are they contributing to your transmission issue? Testing back to back will be best. The dealer testing your truck and several others shows it’s an issue even w/o skids.

Examples of skids causing issues.

3rd Gen Tacomas have an oil temp sensor and overheat warning for the front diff. Toyota possibly deemed mpg more important than cooling the front diff.

Some AWD 4-Runners received serious cooling vents and ducting. Obviously there was some cooling issue here… a grill fed duct and vent.

 

I’m just gonna beat my truck and see what happens. It’s already scratched and beat up getting deep into the forest. While I wish I had the good old v8 packaged in this new body, this is a new era and gotta roll with it.

 

The good old V8 package (Gen 2.5 anyway) runs hot too. They have come up with an add-on external transmission cooler (oil/air) to resolve the issue.

 

Sorry for the frustrations. My '17 4Runner is a better vehicle for 70% of what I do. But it doesnt allow me to just toss and inhale stuff in the bed and not worry about it. You need to be careful not to scratch and mar the inside. Yeah you can put a full enclosure inside but still.
And it returned 10.5 l/100 on my last trip fully loaded. Thats 22 mpg. The Tundra would have returned 19-20 mpg. So @Terndrerrr
I think 19 is very efficient ? very happy with it.

Yes my 4Runner has that opening in the skid plate. Calling it AWD however is not the right term fwiw. You don't have 4Hi and 4Low with AWD. There is a reason Toyota uses an "F" for Full time 4wd on the shift knob. Just saying.

 

It might be my ignorance, but I take little comfort in this idea that the fluid can handle higher temps these days.

Does heat still adversely affect seals and metal surfaces inside the transmission, even though the fluid may not break down as quickly? Are there still areas varnish will build up where we don't want it?

It seems to me that the adverse effects of high temps and old fluid are still possible even with modern ATFs.

 

The secret is there isn't as much oxygen interaction anymore. Deleterious oxidation takes much much much longer.