Towing with a 200-series Toyota Land Cruiser (17 Viewers)

[2021 LC200]

I suspect Toyota voluntarily derates because of added equipment which increases vehicle weight. They probably did the SAE test with an LC and rather than re-run the test with the LX they simply subtract the impact of the added weight, since TW must be 10%. They likely figured few LX owners will tow so it’s not worth repeating the test.

If you want to read the ins and outs of J2807, have fun:

https://fifthwheelst.com/documents/tow-test-standards-2016-02.pdf

For the 16+ models the LC is stated as 8100 lbs of tow capacity and the LX at an unexplainable 7000 lbs, unless the info I looked at is wrong all together.

How is that a test with a LC and then applying it to a LX?

Maybe I misunderstand the point you are trying to make.

 

[radman]

An interesting thing highlighted recently by @radman is how tranny temps remain lower in Normal mode instead of ETC PWR. It would be interesting to understand if this could eek out more MPGs under towing.

I almost exclusively use ETC PWR when towing and haven't really compared. The lower temps suggest that normal mode is more aggressive to lockup the torque converter which makes sense. More lockup reduces temps, but it would also impact efficiency. IIRC, ETC PWR when not towing can make almost 1 MPG difference. And when towing, 1MPG is 10% more fuel efficiency which can be a big deal.

I do like the more aggressive throttle mapping of ETC PWR which is less effort when really heavy. It should hold gears out longer which again helps. When the TC is unlocked, is does create more dynamic gearing. All of which is helpful as designed. At the trade of efficiency.

It does make sense and perhaps understanding that can be an opportunity to eke out more MPG, if desired. Will have to give that a whirl next time.

Well, I can confirm that ECT PWR had me trending ~4-5 degrees warmer AT temp and considerable heat radiation from the center console area.

I initially thought my cool box causing the heat, so I shut it off only to discover that everything in the box was piping hot.

All this happened while pulling a ~2,500lb trailer through Texas Hill country … flat land compared to the Colorado passes I was headed to. At this point, I wasn’t too concerned with the transmission overheating, but rather more annoyed at the heat radiating to my hip and arm.

During a fuel stop, I decided to flip PWR back to normal and immediately noticed AT temp drop back down to normal range, heat had stopped, and the hills were getting bigger….

I did eventually flip PWR back on and noticed the +5* temp trend and console heat reappear.

I wouldn’t say it’s definitive, but for my specific setup (trailer, weight, 35s, stock gears) ECT normal was better.

I drove straight home, 17 hours, and never had the console heat return.

I keep a Flir One with me, and clocked the console heat at 107*

 

[JohnPW]

Well, I can confirm that ECT PWR had me trending ~4-5 degrees warmer AT temp and considerable heat radiation from the center console area.

I initially thought my cool box causing the heat, so I shut it off only to discover that everything in the box was piping hot.

All this happened while pulling a ~2,500lb trailer through Texas Hill country … flat land compared to the Colorado passes I was headed to. At this point, I wasn’t too concerned with the transmission overheating, but rather more annoyed at the heat radiating to my hip and arm.

During a fuel stop, I decided to flip PWR back to normal and immediately noticed AT temp drop back down to normal range, heat had stopped, and the hills were getting bigger….

I did eventually flip PWR back on and noticed the +5* temp trend and console heat reappear.

I wouldn’t say it’s definitive, but for my specific setup (trailer, weight, 35s, stock gears) ECT normal was better.

I drove straight home, 17 hours, and never had the console heat return.

I keep a Flir One with me, and clocked the console heat at 107*

View attachment 3583023

View attachment 3583024

Interesting. I’m curious if you see a temp difference with ETC PWR engaged when not trailering?

I run ETC PWR all the time, whether trailering or not…I prefer the shift characteristics. But mine is a stock truck on P rated tires. My towing is a 5k boat & trailer. I assumed I was doing the transmission a favor with ETC PWR while towing, but maybe not.

 

[LX Cruiser]

For the 16+ models the LC is stated as 8100 lbs of tow capacity and the LX at an unexplainable 7000 lbs, unless the info I looked at is wrong all together.

If the 16+ LX has 110 lb more equipment on it, then it seems that’s how they arrived at 1100 lb lower tow capacity. It makes sense assuming a tongue weight of 10%.

I'm not saying they’re right or that it’s a rigorous way to de-rate higher trim or more equipped models; it just seems that this is what they did rather than test every trim and every configuration of every make/model.

Test the base model, then de-rate the trims with added equipment according to how much more they weigh.

 

[linuxgod]

Well, I can confirm that ECT PWR had me trending ~4-5 degrees warmer AT temp and considerable heat radiation from the center console area.

I initially thought my cool box causing the heat, so I shut it off only to discover that everything in the box was piping hot.

All this happened while pulling a ~2,500lb trailer through Texas Hill country … flat land compared to the Colorado passes I was headed to. At this point, I wasn’t too concerned with the transmission overheating, but rather more annoyed at the heat radiating to my hip and arm.

During a fuel stop, I decided to flip PWR back to normal and immediately noticed AT temp drop back down to normal range, heat had stopped, and the hills were getting bigger….

I did eventually flip PWR back on and noticed the +5* temp trend and console heat reappear.

I wouldn’t say it’s definitive, but for my specific setup (trailer, weight, 35s, stock gears) ECT normal was better.

I drove straight home, 17 hours, and never had the console heat return.

I keep a Flir One with me, and clocked the console heat at 107*

View attachment 3583023

View attachment 3583024

Looks like you’re in 5th gear and the torque converter is unlocked (given the difference between pan and torque converter temp). I bet in 4th gear with the TC locked your temps would be the same.

 

[linuxgod]

If the 16+ LX has 110 lb more equipment on it, then it seems that’s how they arrived at 1100 lb lower tow capacity. It makes sense assuming a tongue weight of 10%.

I'm not saying they’re right or that it’s a rigorous way to de-rate higher trim or more equipped models; it just seems that this is what they did rather than test every trim and every configuration of every make/model.

Test the base model, then de-rate the trims with added equipment according to how much more they weigh.

Yeah this is the point I was trying to get to. They tested the LC, then did a calculation based on the LC of what the LX should be rated at given the SAE rules. It doesn’t mean the LX isn’t capable of towing more, just that they didn’t test it and thus the capacity has to be derated per the SAE calcs

 

[LX Cruiser]

Yeah this is the point I was trying to get to. They tested the LC, then did a calculation based on the LC of what the LX should be rated at given the SAE rules. It doesn’t mean the LX isn’t capable of towing more, just that they didn’t test it and thus the capacity has to be derated per the SAE calcs

Yep, same point I was getting at about a week ago. Still weird that the vehicle isn’t limited by payload first like almost every half ton truck in existence.

To satisfy the newly adopted standard. It penalizes higher trim, more fully-loaded models. 150 lb more stuff on the LX compared to the LC? That means 150 lb less tongue weight capacity which means 1500 lb less trailer weight.

 

[skrypj]

Yep, same point I was getting at about a week ago. Still weird that the vehicle isn’t limited by payload first like almost every half ton truck in existence.

Only trucks with very high tow capacity and decently high trims are payload limited, Tundra excluded. My 2014 F150 Lariat had virtually every option but had 1560 lbs of payload so it was capable of towing its full 11,100 lb rating according to J2807.

The new F150’s have more payload than before. My equivalent Lariat now is probably closer to 1700 lbs payload which means, unless you have a truly max tow package truck, even a well optioned F150 is not payload limited up to 13200 lbs.

 

[eatSleepWoof]

Well, I can confirm that ECT PWR had me trending ~4-5 degrees warmer AT temp and considerable heat radiation from the center console area.

I initially thought my cool box causing the heat, so I shut it off only to discover that everything in the box was piping hot.

All this happened while pulling a ~2,500lb trailer through Texas Hill country … flat land compared to the Colorado passes I was headed to. At this point, I wasn’t too concerned with the transmission overheating, but rather more annoyed at the heat radiating to my hip and arm.

During a fuel stop, I decided to flip PWR back to normal and immediately noticed AT temp drop back down to normal range, heat had stopped, and the hills were getting bigger….

I did eventually flip PWR back on and noticed the +5* temp trend and console heat reappear.

I wouldn’t say it’s definitive, but for my specific setup (trailer, weight, 35s, stock gears) ECT normal was better.

I drove straight home, 17 hours, and never had the console heat return.

I keep a Flir One with me, and clocked the console heat at 107*

View attachment 3583023

View attachment 3583024

Wow, that's very, very cool!

My gut says that 35s on stock gears will be a significant factor here.

 

[LX Cruiser]

Only trucks with very high tow capacity and decently high trims are payload limited, Tundra excluded. My 2014 F150 Lariat had virtually every option but had 1560 lbs of payload so it was capable of towing its full 11,100 lb rating according to J2807.

The new F150’s have more payload than before. My equivalent Lariat now is probably closer to 1700 lbs payload which means, unless you have a truly max tow package truck, even a well optioned F150 is not payload limited up to 13200 lbs.

Yeah, I’m thinking mostly of all the ones I see on the road. Higher trim, crew cab 4x4s. Ford has been really good about reducing curb weight for extra payload capacity. They’re about the only ones you can tow heavy and still have your family in the truck with you. I still wouldn’t ever want to pull 13k in a truck that weighs less than 5k.

 

[CreeperSleeper]

Just some State Park RV-ing with friends for Spring Break...

 

[skrypj]

Park City UT to San Diego. Boondocked south of Vegas to break up the drive.

California is the worst place to tow. I’d rather tow in Wyoming in 50mph winds than deal with the drivers in CA and the silly 55 mph towing speed limit.

 

[Matthew810]

Interesting. I’m curious if you see a temp difference with ETC PWR engaged when not trailering?

I run ETC PWR all the time, whether trailering or not…I prefer the shift characteristics. But mine is a stock truck on P rated tires. My towing is a 5k boat & trailer. I assumed I was doing the transmission a favor with ETC PWR while towing, but maybe not.

I run ETC power all the time on my 13 LX with 33s and a sensor lift. Feel like it just shifts at better spots. I’ve not noticed the heat issue but I really only tow my 2 waverunners on their trailer and not for more than 90 minutes at a time. I’ll have to pay more attention and run the torque app next time.

 

[skrypj]

Just wrapped up a nearly 1600 mile trip from SLC to San Diego and back. LX did great with the only real issue being the fuel tank size. 24.5 gallons is just about the range I can reliably tow between my 7 year olds pee breaks but a few times I could have probably pushed another 30 minutes had I had a few more gallons. Especially once I get into a headwind and am low 8’s or 7’s mpg wise.

On a separate note, the high transmission temperatures seem to be because the torque converter never locks in 4th gear or below. If I pull a grade in 5th I’m not even sure it breaks 200F but as soon as I drop to 4th and pull for more than a couple minutes I am in the 230’s or 240’s

First screen shot is 5th. You can see the TC lockup PID second row from the bottom on the right as a 1.

Heres 4th about 30 seconds after at the same speed, no lockup.

So I think the best solution is probably adjusting the tuning to lock the TC above 55mph as opposed to throwing more cooling at the issue. I really don’t see a reason to have the TC unlocked in 4th at 60-65mph.

 

[linuxgod]

Just wrapped up a nearly 1600 mile trip from SLC to San Diego and back. LX did great with the only real issue being the fuel tank size. 24.5 gallons is just about the range I can reliably tow between my 7 year olds pee breaks but a few times I could have probably pushed another 30 minutes had I had a few more gallons. Especially once I get into a headwind and am low 8’s or 7’s mpg wise.

On a separate note, the high transmission temperatures seem to be because the torque converter never locks in 4th gear or below. If I pull a grade in 5th I’m not even sure it breaks 200F but as soon as I drop to 4th and pull for more than a couple minutes I am in the 230’s or 240’s

First screen shot is 5th. You can see the TC lockup PID second row from the bottom on the right as a 1.

View attachment 3618893

Heres 4th about 30 seconds after at the same speed, no lockup.

View attachment 3618891


So I think the best solution is probably adjusting the tuning to lock the TC above 55mph as opposed to throwing more cooling at the issue. I really don’t see a reason to have the TC unlocked in 4th at 60-65mph.

If you have the 8 speed you should tow mostly in 6th. The TC won’t lock in most lower gears.

 

[2021 LC200]

If such a TC lock up mod exists for the 8 speed (AE80F), I would be very, very tempted.

Sofar I have only seen for the 6 speed in Australia.

 

[skrypj]

If you have the 8 speed you should tow mostly in 6th. The TC won’t lock in most lower gears.

I do but it’s not gunna pull a 7% grade in 6th gear. It’s going to drop to 4th or 3rd and that’s when the temps spike.

The two times I had temps issues with the trans were pulling Cajon Pass out of San Bernardino to Victorville and then the climb from St George UT to Cedar City. Both are very long with some 6+% sections.

You can see in my screen shots 4th puts the engine at 3500 rpm and that was at ~65 mph.

 

[linuxgod]

I do but it’s not gunna pull a 7% grade in 6th gear. It’s going to drop to 4th or 3rd and that’s when the temps spike.

The two times I had temps issues with the trans were pulling Cajon Pass out of San Bernardino to Victorville and then the climb from St George UT to Cedar City. Both are very long with some 6+% sections.

You can see in my screen shots 4th puts the engine at 3500 rpm and that was at ~65 mph.

Yes the 6 speed does the same in 2nd and 3rd. Toyota feels it’s ok so long as you’re under ~270F

 

[skrypj]

Yes the 6 speed does the same in 2nd and 3rd. Toyota feels it’s ok so long as you’re under ~270F

This is the same Toyota that says its lifetime trans fluid?

I can just tweak the tune slightly to make it lock up 3rd and 4th above 55mph and it will be a non-issue.

 

[TeCKis300]

This is the same Toyota that says its lifetime trans fluid?

I can just tweak the tune slightly to make it lock up 3rd and 4th above 55mph and it will be a non-issue.

Do you have a tool to tune that?

I'm not sure I would characterize any of this as an issue. It's normal for it to lock and unlock as it sees fit. Unlock is a tool to smooth out power delivery. It also works as a virtual gear between gears for more mechanical advantage. That the tranny fluid warms up is no big deal within the normal range. It will get to a threshold where the tranny ECU will get more aggressive about locking to manage temps. I've seen it lock all the way down to 2nd gear (on my 6 speed).

Agree heat is definitely generated by unlocking. It unlocks on downhills too under engine breaking. The other factor is how much power is being pushed through the tranny. Try pushing 350hp+ for minutes and yes, things get warm, even locked. I would also say to use RPM to your advantage. The party gets started at 3500 RPM. Relatively less combustion pressure for the same output at higher engine speeds, and more fluid circulating in the engine and tranny.