Transmission Overheating - anyone else?

[fuzznuts]

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.

 

[TAP34]

Thank you for putting this out

 

[phillips_th]

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.

 

[RUN-8]

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.

 

[ultane]

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..

 

[RUN-8]

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.

 

[KyLandcruiser]

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.

 

[RUN-8]

I was pleasantly surprised by that too. To lock it I had to manually activate the center lock.

 

[lcq]

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.

Transmission temps on LC 250

Question for other owners out there, what have you seen with transmission temps? Towing, off road, hot days etc? Mine creeps up to the pic below in 4 low and driving uphill gravel roads (in a spirited manner) in the high country. The ambient temp is rarely above 70 when I'm up there. Not too...

forum.ih8mud.com

 

[Robbie]

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

 

[BKLC]

I have a 2024 LC/LC trim w/premium. Purchased it mid-August and it has just under 9k miles (oil changed @ 200, 2k, 5k miles)

Today, I took it a circular trail starting with a section called Gobblers Knob (rated 3 on OnX Off Road - see attached screenshots w/red trail-line and video) ~15mile trail climbing from 4200-6500ft in elevation. Mostly dirt/gravel roads, I spent most of the climb under 5-10MPH

During the ascent, my transmission temperature gauge hit 3/4 - just under the red. I pulled over to let it cool off and my car reeked of a burning smell. I was driving/drove the entire trail in ECO, 4hi, and the temperatures seemed to climb during the ascent which was roughly 5 miles, 4000 ft in elevation, @ 5-10mph. The middle section was relatively flat, and the back half was mostly descending thus I was just managing the brake (transmission temps didn't rise)

This is my first time off-road in this car at all, and ever
1. Did I do something wrong? Should I have driven this in 4-lo? I wasn't slipping at all and didn't need to change the drive mode
2. What would you do next, if you were me? Should I contact my dealer/toyota?

 

[TakaraLC]

I have a 2024 LC/LC trim w/premium. Purchased it mid-August and it has just under 9k miles (oil changed @ 200, 2k, 5k miles)

Today, I took it a circular trail starting with a section called Gobblers Knob (rated 3 on OnX Off Road - see attached screenshots w/red trail-line and video) ~15mile trail climbing from 4200-6500ft in elevation. Mostly dirt/gravel roads, I spent most of the climb under 5-10MPH

During the ascent, my transmission temperature gauge hit 3/4 - just under the red. I pulled over to let it cool off and my car reeked of a burning smell. I was driving/drove the entire trail in ECO, 4hi, and the temperatures seemed to climb during the ascent which was roughly 5 miles, 4000 ft in elevation, @ 5-10mph. The middle section was relatively flat, and the back half was mostly descending thus I was just managing the brake (transmission temps didn't rise)

This is my first time off-road in this car at all, and ever
1. Did I do something wrong? Should I have driven this in 4-lo? I wasn't slipping at all and didn't need to change the drive mode
2. What would you do next, if you were me? Should I contact my dealer/toyota?


View attachment 22560View attachment 22562
View attachment 22563

Torque converter is probably slipping going uphill at 5-10 MPH. What was your RPM during the climb?

You could try LO or switch the gear to manual and use a lower gear at higher RPM to see if it prevents slip.

 

[RUN-8]

I would personally use low range on that do the torque converter stays locked.

 

[BKLC]

My RPMs were low, nothing spiky or super high/noticeable...

going forward I should do that on 4lo? I hope I didn't cause any permanent damage, figured it wasn't much different from driving up a paved driveway at the same speed/distance?

 

[KyLandcruiser]

Move the shifter over to manual shift. I would do 1st gear if going 5 MPH. The vehicle is anticipating a shift so the transmission will slip the torque converter and clutches.

 

[TakaraLC]

My RPMs were low, nothing spiky or super high/noticeable...

going forward I should do that on 4lo? I hope I didn't cause any permanent damage, figured it wasn't much different from driving up a paved driveway at the same speed/distance?

Low RPMs is the problem in this case. Since you are going uphill at a low speed and low rpm, torque converter will slip to prevent the engine from stalling. Torque converter uses some type of “friction fluid” to couple the transmission and engine, so when it slips constantly for a long duration, a lot of heat is generated.

I am not sure how familiar you are with manual transmission, but a good analogy would be driving the truck with clutch half pressed (rather than down shifting), which will overheat the clutch.

So under these conditions it is better to put the transmission in manual mode and down shift. You could also try using sport mode, which makes the transmission hold on to lower gears. I think using eco mode was also partially responsible in your case since it tries to keep RPM low. 4LO would also work, but I think it would not come to that if you keep RPMs high in 4Hi.

 

[RUN-8]

My RPMs were low, nothing spiky or super high/noticeable...

going forward I should do that on 4lo? I hope I didn't cause any permanent damage, figured it wasn't much different from driving up a paved driveway at the same speed/distance?

I doubt you caused any damage at all.

Low RPM’s combined with low speeds will usually = the torque converter unlocking to allow the torque converter to do torque converter things like acting as a fluid coupler. The reason the torque converter will stay unlocked is that your speed is going vary and the programming at these low speeds will call for the torque multiplication ability of the unlocked converter to allow you to move around with low engine load/output in low gears.

Imagine doing this with a manual transmission without a creeper 1st gear, you would be slipping the clutch constantly, guess what that would do to the clutch on a manual transmission? If you guessed get it really hot and damage it you win a prize!

In your automatic transmission this works the fluid in question, transmission fluid, and when you work that fluid by imparting energy from the engine through an impeller it will build up heat in that fluid.

By selecting low range on the transfer case a modern electronic control transmission knows that the torque multiplication is now being achieved with the transfer case. So it will signal the torque converter to stay locked. This should reduce heat build up in the transmission fluid because the torque converter impeller isn’t working the fluid.

Hope this explanation is both helpful and effective in real application.

 

[BKLC]

I can drive a manual, so I understand your explanation a bit. But the torque converter and multiplication pieces are basically a foreign language to me lol. I appreciate both of your help and input though! I can't tell if RUN-8 is joking when saying he doubts I caused any damage at all haha.

It smelled like something was cooking a little bit, but I pulled over and stopped my car to let my dogs out anyway, probably 2-3 times so the car got to chill out a bit. On the way home I hopped on the freeway and it rode normally.

 

[RUN-8]

If you weren’t in the red on temps I wouldn’t worry about it.

When I did my little lest at under 1000 miles it had some definite odors coming off the vehicle. New trucks take some time to burn off all the assembly and shipping preservatives and grease, running down the highway isn’t necessarily going to get that done.

 

[TAP34]

I have a 2024 LC/LC trim w/premium. Purchased it mid-August and it has just under 9k miles (oil changed @ 200, 2k, 5k miles)

Today, I took it a circular trail starting with a section called Gobblers Knob (rated 3 on OnX Off Road - see attached screenshots w/red trail-line and video) ~15mile trail climbing from 4200-6500ft in elevation. Mostly dirt/gravel roads, I spent most of the climb under 5-10MPH

During the ascent, my transmission temperature gauge hit 3/4 - just under the red. I pulled over to let it cool off and my car reeked of a burning smell. I was driving/drove the entire trail in ECO, 4hi, and the temperatures seemed to climb during the ascent which was roughly 5 miles, 4000 ft in elevation, @ 5-10mph. The middle section was relatively flat, and the back half was mostly descending thus I was just managing the brake (transmission temps didn't rise)

This is my first time off-road in this car at all, and ever
1. Did I do something wrong? Should I have driven this in 4-lo? I wasn't slipping at all and didn't need to change the drive mode
2. What would you do next, if you were me? Should I contact my dealer/toyota?


View attachment 22560View attachment 22562
View attachment 22563

First I would get it out of ECO that doesn’t sound right