Why were you using manual mode and monitoring transmission temp if it was just a normal road? This seems problematic under the conditions. If you can replicate the problem, I’d see what Toyota can do for you.
Transmission Overheating - anyone else?
- Thread starter fuzznuts
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WookieBait
Active member
Because I wanted to
After reading all these accounts I was watching pretty closely on our first off-road trip with lots gold to climb. I never saw the temp go up much. I’m thinking it’s a QC problem with some transmissions that are always troublesome. But only Toyota has the data to really know.
WookieBait
Active member
Just for data, did you use 4lo or just kept it in 4hi?
A mix of the two, on lot of the uphill roads 4lo would have been too slow.
Just out of curiosity, did you use manual or drive?
Drive.
You have plenty of warranty left. Give it a little time. Maybe Toyota will fix this, or put out a TSB…
Interesting posts. I took my new (2,000 miles) LC 1958 out yesterday for what, by all accounts, was a "moderately difficult", three-hour drive at 70 degrees F., and, after a few miles, a few hills and a few descents, my "high transmission fluid temperature" warning message came on. The trip leader radioed me to put it in 4L for a few minutes to see if that helped. It did, but this rig ought not to overheat under these conditions. Have made a date to take it to a dealer on Monday for an investigation.
Be forewarned - the dealer won't do anything unless you can replicate it with them. My dealer claimed that the computer does not log any overheating incidences - so they saw no issues. They suggested I take a picture of it next time it happens to prove it. Haven't got around to that yet. Don't think that would change much though since they have to replicate the issue. Hopefully you have photo evidence to show them the warning message, and a nearby hill to show them the issue.
Today I was playing with an app called "Car Scanner" using the Carista bluetooth adapter (shoudl work with most?), it can show you real time data on your infotainment screen via CarPlay, and more importantly it also lets you export data as (a very messy) csv.
I've been focusing on EGT and DPF related stuff, but you might be able to get trans temps and lock up state out of it too. (You have to pick specific for dashboard #2 for it to record things, I think.)
I think this might come in handy for analysing and understanding what is actually happening.
It doesn't seem entirely reliable, I have noticed that some some readings like speed disappeared after 12 mins or so, I haven't spent much time with it, but yeah, just thought it might be useful.
I've been focusing on EGT and DPF related stuff, but you might be able to get trans temps and lock up state out of it too. (You have to pick specific for dashboard #2 for it to record things, I think.)
I think this might come in handy for analysing and understanding what is actually happening.
It doesn't seem entirely reliable, I have noticed that some some readings like speed disappeared after 12 mins or so, I haven't spent much time with it, but yeah, just thought it might be useful.
I'm quite sure there is freeze frame data in the ECU for any over temp warning, likely the tech is only looking for codes. I've been through mine few times in Toyota GTS+ and everything seems to log freeze frame events or a ROB event (Record of Behavior).
I'm not a 100% a warning would do this but anything that sets a pending, temporary or permanent code stores the DTC and either a freeze frame, ROB or both along with the DTC regardless if it will illuminate the check engine light.
I'm not a 100% a warning would do this but anything that sets a pending, temporary or permanent code stores the DTC and either a freeze frame, ROB or both along with the DTC regardless if it will illuminate the check engine light.
I’m curious what the threshold is for overheating for the dealer? This was my reading over the summer.
FYI this taken with the OBD2 reader and the CarScanner app shown on Apple CarPlay.
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Anything at 240F or more in the sump is not good, not sure what the parameters are for warning and overheated on this platform?
Ideally it sump temp is at or within a few degrees of the coolant temp.
Ideally it sump temp is at or within a few degrees of the coolant temp.
Mine is the same everytime I take her to the trails. Even when placing on Manual (though better), it is still going all the way up. To avoid overheating, I will either stop to pee and let my girls walk for a little, or swutch to turtle mode (4 LO) for a bit until it reaches 220 or below, and then REPLAY!!!
on other threads, people were saying the torque converter is the reason for overheating. mine does the same, need to use 4LO only - temps rise as soon as its in 4HI
I've driven over 300-miles off road. 4LO through a vast majority of it using manual mode for gear selection. If you're in 4H, you're asking for issues with this platform (that likely needs a large external cooler w/ fan). Transmission temperature in 'turtle mode' (4L) is perfect. Anything over 15-20 mph, I'm in 4H, also in manual mode. Doing this, I've never had any issues with temperatures.
I wouldn't touch it until it's well out of warranty coverage. The dealer will absolutely void the transmissions warranty if they find an external cooler. Should it be like that, of course not, but they will fight like Hell to make sure they aren't the ones paying to replace the transmission when it fails.
I wouldn't touch it until it's well out of warranty coverage. The dealer will absolutely void the transmissions warranty if they find an external cooler. Should it be like that, of course not, but they will fight like Hell to make sure they aren't the ones paying to replace the transmission when it fails.
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The first response I can make to you on such an obvious reason for your transmission overheating is why do you think Toyota has fitted a low range transfer case? And the second question is why do you think Toyota have fitted an 8 speed automatic?
Bub
With your logic you don't want to use the tools properly so they now show signs of breaking.
An automatic torque converter can only handle a finite amount of load displayed as heat through transmission oil.
Either use your vehicle in its design parameters or you will break it, simple as that.
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