Transmission Overheating - anyone else?

Understand your position; it doesn’t help the product or the manufacturer though not produce the failure or it just could be an outlier. I have an LC250 1958 and nearly at 5k having taken on trips and Offroad conditions not seen anything like overheating. Hope you find what you enjoy and is reliable.
I offered the vehicle to Toyota and service centers to keep the vehicle and do what they want with it. I shared the videos and data I collected and the exact mountain roads driven that caused those conditions.

If Toyota or the dealer/service center aren’t interested enough to care about their product then it’s hard for me to. Ultimately it’s not worth my time or energy.

I will keep lurking on the forums as I will be curious to see if I just had an outlier or not.
 
TXD - 0701221AAA
RXF - C462051A36AA
RXD - 3008
MTH - 00090005FFD8



Feel free to DM me and I can share the route, it includes driving through Golden Gate Canyon State Park



69F on cold start this morning after sitting overnight.
I've pulled my Taxa Cricket (200lbs) up to Golden Gate Park up Canyon Drive through Boulder (10% grades and around it). Golden Gate. There are several roads where trailers are not allowed (20% grade) that we drove on without the trailer. My transmission temps stayed dead center going up hill and down with 200lbs trailer.
 
To test this transmission overheating issue out I decided to take my Land Cruiser LC trim up the nearest crappy gravel road leading to a state game production area. I just got back from running up and down twice. Once in 4Hi and once in 4Lo.

Outside ambient temperature was 44F.

Maximum speed on this “road” is about 19-20 MPH you really don’t want to drive any faster. Average speed is more like 11-13 MPH because it’s a rutted out mess. Plus it’s a steep grade in a few spots climbing from 3400 to 4300ft of elevation in about 2 miles or so.

I had no transmission heat issues at all.

The run I made in 4Lo wasn’t some terrible ordeal of the engine being redlined the whole time. I don’t think 3000-4000 RPM is the end of the world, redline is a bit over 6000 RPM. The truck is perfectly capable of running over 20 MPH in 3rd gear in 4Lo frankly I had no desire to drive any faster because the road is rougher than hell.

At no point in 4Lo did the engine ever make any boost on the turbo. I suspect the waste gate is just left open in 4Lo. The electric motor did assist quite a bit. I’m not sure why the OP feels the truck lacks adequate power off-road, I observed no issues in or out of 4Lo.

I was interested to test out the sway bar disconnect, and it makes a difference in ride quality at the very least.

For anyone who has doubts the center differential is not automatically locked in 4Lo, so there is no binding or crabbing while turning. This feature is amazing. 10/10.
 
Maximum speed on this “road” is about 19-20 MPH you really don’t want to drive any faster. Average speed is more like 11-13 MPH because it’s a rutted out mess. Plus it’s a steep grade in a few spots climbing from 3400 to 4300ft of elevation in about 2 miles or so.

I had no transmission heat issues at all.

At no point in 4Lo did the engine ever make any boost on the turbo. I suspect the waste gate is just left open in 4Lo. The electric motor did assist quite a bit. I’m not sure why the OP feels the truck lacks adequate power off-road, I observed no issues in or out of 4Lo.
Thank you for doing this! Another set of worry beads that I can now throw away..
 
Your results may vary.

I think the OP either had a malfunctioning LC or was just not going to be happy with it no matter what.
 
The center diff lock not automatically activating in 4 Lo is definitely new to me. I have an 99 lx470 and the center diff automatically locks when shifter is moved to 4 Lo.
 
I was pleasantly surprised by that too. To lock it I had to manually activate the center lock.
 
My 1958 has the transmission overheating issue as well very similar to OP. I think I may have been mentioned earlier in this thread from my posts on IH8MUD. It’s overheated once on a high elevation 5 mph rough road in 4hi while my wife was driving solo. Less than a mile in. In 4lo it always ran hot this summer. Will be testing more next summer or possibly in Moab this winter. I’ve posted about it a few times over on MUD. Will add more later but wanted to put a note on this thread that this isn’t a one off. A few of these LC do have a transmission issue to be aware of. It simply shouldn’t overheat the trans on a short off road with one driver and 200 pounds of gear, no matter what the transfer case setting is imo.

 
I wanted to share my experience with the community in case others are having similar issues.

My Land Cruiser (1100 miles) is reporting overheated transmission fluid under certain conditions that my service center has been unable to replicate and therefore do anything about especially with the absence of any thrown codes.

On relatively slow (10-45 mph) winding paved and gravel roads that head up into the mountain near me, the transmission temp gauge gradually climbs to about 3/4 of the way to the red. If I continue on a dirt road that also puts the vehicle under load at slow speeds going up a hill the gauge will eventually hit the red and I will get a message that the transmission fluid temp is high and to pull over safely. This dirt road seems to be the trigger that actually overheats the transmission. The section of off-road trail is not tough trail and does not require low-range or even locking the center diff. Kias/Subarus have been on this part of road in the past.

I currently only able to read transmission temp sensor #1 from the ECU and between 245F and 250F the vehicle is overheated. At around 235 the gauge is 3/4 of the way towards the red. At one point I watched the temp gauge, in the span of about 4-5 seconds, go from blinking red (overheated) then drop to the middle point and then move back up to just below the red all while not moving.

As another data point, I am routinely in the 200F-215F while putzing around town which seems to be on the warm side however I do not really know what the expected normal operating temp is. I have also noticed that from about 130F to 215F the transmission temp gauge remains in the middle.

I am not able to replicate this issue while driving in the city or highway driving in the mountains.

Is anyone else experiencing anything similar? I would be curious to know what temps others have been observing around town and under load like mountain or light off-road driving.
I found this resource in Sema Show
 

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