Transmission overheating 3rd gen Tacoma

Hey guys. I have a 2019 TRD Off- Road. Have about 2500 miles and took it light off-roading the other day.... In 2 wheel the whole way until got to a somewhat steep incline Up a dirt hill. So I put her in N and switch to 4L. The. Proceed to climb up the hill and engine cuts out and it says transmission overheating. Odd... 50 degrees outside.... going maybe 5mph. Engine started back up no problems... Called dealer said they don’t know anything. Thanks for any advice.

 

Usually when that happens it means you have been spinning the hell out of it in heavy deep mud/sand/snow.
Other way you can do it is go to max torque application for a long time, like hooking it to a heavy trailer and pulling it straight up a hill.

If you did it "light off roading" then you need to take it in because something is wrong with the transmission.

 

Possible low trans fluid

Or it’s the TSS problem throwing diff error messages

 

We’re you drifting on the dirt roads or spinning the tires at all? Hope this all get sorted out!

 

Nope, been babying the truck since it’s new. And me too! Thanks!

 

Hasn’t been as common in the 18+ trucks but there was a lot of reports of low tranny fluid from the dealers. Maybe your came a little low. Trip to the dealer sounds like your next step.

 

Low tans fluid has been an issue since the 16 models came out. Take it in, have it looked at and and have them check the fluid level.

 

Welcome to TW!

 

Hello so im wondering what was the issue here with the original post? I was off roading lightly and went up id call a steep rock type hill. I made it half way up in 4L with my rear locker off with ECT mode on. My wheels started spinning and my truck shut off suddenly and flashed a warning but didnt stay on saying something along the lines of transmission oil temp to high or something like that. Now i know i should have had my rear locker on but Im wondering if i should have used my crawl control to take me up the hill or having the ECT mode had something to do with it? This all being said my truck has a total of close to 800-900lbs of mods/gear and is regeared to 5.29 on 35inch tires. Im taking it in to see what the code actually was and most likely a trans flush because it went away so fast but almost positive it said that my trans overheated. I waited a few mins and the truck started fine and backed down the hill very slowly. And proceeded to off road then in the mud and ended up sinking it in the deepest puddle i ever will go in went to my hood in 4H and did more mudding for 2 hrs before i drove home an hour and havnt really driven since. That all being said id appreciate any info you have even if you just want to say i could have done something better. And thank you so much for reading my post!

 

I’m spinning my thinking hat here and think that if the incline was steep enough and long enough, driving in Lo, you may not have been going fast enough to gather enough air flow to cool the transmission.

The A/T works its hardest towing and going up inclines. But when you’re towing, you’re most likely to be going at higher speeds and the higher air flow cools it, then if when you’re in Lo.

And I doubt that it’s low on ATF fluid, as that would have caused other symptoms such as stalling (late shifting) and it is filled correctly at the factory, so barring any leaks that you would see on your driveway it should be fine.

 

Discussed in other threads. Likely anti-stall from roll back or throttle modulation. Happens a lot on steep climbs in 4L

 

Those of you having issues with trans temps should seriously consider investing in an ODBII reader that can be programmed with the TF1 and TF2 temp readouts so you can see, in real time, the impact of terrain and other variables are having on your transmission temperatures. TF1 is the ATF returning from the cooler, TF2 is the ATF leaving the torque converter where the fluid will be its hottest (that is for my 2021 TRD Sport, not sure if that is different for a 2019... something to confirm). I tow a 3500# off-road trailer and I have seen huge spikes in temp while slowly going up and down inclines in 4LO, 4HI, and 2WD.

Remember that your torque converter is a clutch that is slipping when the torque converter is not locked which generates a massive amount of heat. If you are moving relatively slow in 4LO up steep obstacles while the tires are slipping and your engine is revving high while your forward momentum is relatively low with the load on your driveline being crazy high you are creating a situation for maximum trans temps. This is a recipe for a LOT of heat in the converter and at low speeds the trans cooler cannot handle the loads which is why a lot of bubbas that tow put an external trans cooler with a fan inline. That may be why you are seeing the temperatures you are seeing but I have been in some pretty gnarly situations towing my 3500# XOC off road and have never had this happen. If it were me, I would verify your TF1 and TF2 sensors are working properly then buy a scan.gauge.2 or 3 (or similar) to monitor temps regularly, and also research @JoeCOVA 's comment re: anti-stall from rollback or throttle modulation.

An easy way to check your trans fluid without taking it to a mech is to bring it to ~106 - 109 deg F (get the scan gauge first and program in TF1 and TF2 - codes are on their website), then open up the 5MM overflow plug and ATF should very slowly drip out if your fluid is at the proper level. If it doesn't slowly drip out, you are low. Get yourself a cheap bottle pump, pick up the appropriate ATF and the crush washers from your local dealer and fill until ATF slowly drips out. Check out this vid (I know, I know, this dude was banned from promoting his stuff here and many think he is a dick because of his attitude on the forum - but duder takes you through the entire process of changing/replacing ATF in painstaking detail). The 23:03 mark in the linked vid is the process I am describing. Any DIYer with a basic metric socket set can perform this task as long as you have something to see when your Taco trans is near or at 106 deg F.

Hope this helps.

Edits: clarity and spelling.

 

This is all great info/ ideas i am looking into an aftermarket trans cooler with fan and already purchased the scangauge 2. I have an appointment tomorrow at the dealer to pretty much just see what code was thrown and see what they say after that. I didnt do the work but when i regeared to 5.29 dont they change the trans fluid thats how i got it could be at the wrong level?

 

They dont touch the trans on a regear

 

Good to know thanks again will post more as i find things out.

 

I'd be more concerned with the engine stall as the actual issue. The high trans temp is known to momentarily occur after an engine stall from an otherwise normal fluid temperature.

 

See i didnt know that I thought the engine stalled bc the trans warning they both happened at the same time so i thought i was a safety feature for the transmission to not damage itself. So your saying i have 2 issues? I may be confused so the transmission overheat that appeared on my dash was not supported to kill the truck? I should bring up both issues?

 

or none.

 

You have zero issues like Joe said, its literally just the trucks feature. Stalls when rolling back in drive, and it faults to the "high temp warning" to tell you that you are still in drive, and need to shift to neutral or park to start the truck again. The tranny only overheats in extreme cases in 4 low.

 

Thanks everyone buttskevin is correct. Apparently the code that was thrown was high temp but it was because I unknowingly pressed the gas and break at the same time which stalls the truck and throws the high temp code because the trucks was still in drive. I guess i just panicked on the hill. Thanks everyone!