MPGs - Many People Griping - A Foundational Knowledge Primer To Assist in Better Efficiency

[COSmurf]

One common misconception is that lc 4cyl provides better gas mileage at highway speeds than the Lexus gx
Accordin to car and driver 75mph highway testing they both averaged 21mpg
So much for its a harsh 4 cyl , well atleast it delivers on fuel economy

https://www.caranddriver.com/lexus/gx#:~:text=Fuel%20Economy%20and%20Real%2DWorld,economy%2C%20visit%20the%20EPA's%20website.

https://www.caranddriver.com/toyota/land-cruiser-2026#:~:text=The%20EPA%20hasn't%20released,economy%2C%20visit%20the%20EPA's%20website.

https://www.caranddriver.com/toyota/land-cruiser-2026#:~:text=The%20EPA%20hasn't%20released,economy%2C%20visit%20the%20EPA's%20website.

The Car and Driver test flat out says they hold the car at 75 MPH… the fuel consumption at that speed will not be all that different between GX and LC for all the reasons stated previously. The small LC motor can just employ enough boost to deliver the power of a much larger motor like the GX’s. Drop down to 70 or 65 MPH and the fuel consumption between LC and GX at those highway speeds is drastically different. As I said, think of the turbo and hybrid as displacement on demand. The neat party trick however cannot be done in reverse by the GX where it sheds displacement (and pistons) to be anywhere near as efficient as the LC motor because at its baseline, it’s a much larger motor even when driven gingerly. I love that the LC can step up and power the car to near GX levels of HP and Torque for bursts as needed, but then is much more gas efficient the rest of the time. That’s a really nice feature and attribute to possess. The GX engine is way more thirsty for the rest of the time. I also love that the LC achieves that big power not solely through employing more boost, but also incorporating hybrid electric boost so as to not stress the engine as much as would be the case if it went to max boost pressures of say 20-25 without electric vs the 10-15 with electric it runs at.

 

[robsurfskate]

then you don't get overdrive on the highway

then you don't get overdrive on the highway

Hmmmmm. I did not know that. NORMAL driving mode on highway will get it in the higher gear ratio?

 

[robsurfskate]

then you don't get overdrive on the highway

Thanks for the heads up. I need to be in NORMAL mode for highway driving.

 

[GrayBeard]

The Car and Driver test flat out says they hold the car at 75 MPH… the fuel consumption at that speed will not be all that different between GX and LC for all the reasons stated previously. The small LC motor can just employ enough boost to deliver the power of a much larger motor like the GX’s. Drop down to 70 or 65 MPH and the fuel consumption between LC and GX at those highway speeds is drastically different. As I said, think of the turbo and hybrid as displacement on demand. The neat party trick however cannot be done in reverse by the GX where it sheds displacement (and pistons) to be anywhere near as efficient as the LC motor because at its baseline, it’s a much larger motor even when driven gingerly. I love that the LC can step up and power the car to near GX levels of HP and Torque for bursts as needed, but then is much more gas efficient the rest of the time. That’s a really nice feature and attribute to possess. The GX engine is way more thirsty for the rest of the time. I also love that the LC achieves that big power not solely through employing more boost, but also incorporating hybrid electric boost so as to not stress the engine as much as would be the case if it went to max boost pressures of say 20-25 without electric vs the 10-15 with electric it runs at.

This is spot on.

There's a reason high performance piston engine aircraft (at their pinnacle think end of WW2) almost universally used superchargers or turbo/superchargers. Weight. As much as we worry about MPG, for aircraft engine size and weight were killers, so getting more out of an engine by forced air induction on demand was so crucial as to be essentially mandatory.

In my growing experience with the LC the key factors that don't compete so much as intertwine for better MPG are absolute speed and consistency of speed.

So far my best tank MPG has been just over 26 MPG, and that was prior to the first break in oil change. My MPG on average has continued to just go up as I close on 5K miles. That 26 MPG was from a string of very fortuitous commutes during spring break, which meant much less traffic on the roads and a steady cruise speed be it on the highway or city streets (my 25 mile one way commute is about 50/50 though I can bias it depending on traffic). I was still in the break in period and didn't exceed 65 mph at all on that tank, and was generally at 60 mph on the freeway and 35-45 on the city streets, but essentially never had to slow and accelerate for traffic and made most lights.

Now I still try to keep at or below 70 on the freeway as I've experienced much better MPG at 65-70.

But I just did the first road trip last weekend even though it was short. About 2 hours up, 2 hours back, and if you've ever driven I-64 from Hampton Roads to Richmond you know that it's slow and go for a good portion even without accidents and traffic, but also that if you're doing less than 70 in the right lane when it's "go" you're going to get run over, rear ended, shot, or some combo of the three. So I averaged between 70 and 80 on the way up with normal slow and go and still got about 24 MPG while the trip back had stop and go behind two accidents but still got about 23 MPG.

On individual stretches (10 miles or more) where I could hold a steady 65 or 70 I was flirting with 28 MPG on the gauge, so I fully believe it's doable. I should note that all of my commuting is done alone, but on the trip I had four adults and 9 year old in the car, so solo my numbers would have been marginally higher I believe.

On the flip side, this morning's commute was almost zen like, hitting almost every single light green and free flowing traffic on the highway portions, and my trip average climbed up to 25.2 MPG with city driving at about 40 mph. So having the turbo to boost performance (no pun intended) lets the LC work like a larger engine on the freeway, but a smaller engine on the street.

Still loving the LC.

And the one bad light I did hit this morning, just as it went red, is two minutes long. But being a hybrid the engine shut down and I didn't use any gas, plus the guy in the LX 460 next to me got to ask how I liked the LC because he was thinking of getting one.

 

[Viktorv1961]

Not buying it from car and driver. I can get 29 MPG highway cruising at 65 MPH. Doubt the GX can do it.

The LC iforce max hybrid is a fantastic drive train if you know how to use it. Then you can just take the GX MPG and add +8 MPG.

There are many sources in this forum and beyond that discuss how to achieve it.

All stock LC LC in "Normal" mode. I cannot get even close to 29MPG. Last week I purposely drove at 64-67 mph on 100 miles round trip. As a result-22.1 MPG. But I can get about 27-28mpg on country roads driving about 50 mph.

 

[SlickLC]

eco mode did net me more mpgs on local roads under 55. i was averaging 16-17mpg in normal mode and 17-19 in eco mode. gonna have to do more testing on highway.

 

[Blue Sky]

I have an anecdotal observation regarding the adaptive cruise control, distance spacing and a potential effect on MPGs.

I did a 2k out-and-back through the midwest a few weeks back. I used the adaptive cruise control for around 95% of the interstate driving. What I noticed is the distance setting regarding vehicle spacing seems to have an impact on MPGs.

At the ACCs maximum distance setting (4 blue bars) the LC held a more controlled speed while using almost no braking and minimal throttle to maintain speed. When traffic increased or I was passing through city centers I set the bars to 1 or 2 to decrease spacing between vehicles. While the ACC did an exceptional job at maintaining the distance, I noticed the brakes were being used quite a bit and then throttle/turbo was being applied to compensate for over correction. Multiply this brake/accelerate cycle by the tens to 100s over the course of a trip and I can see a mpg penalty adding up.

 

[BlueCruiser]

Keep trying! It is definitely possible to achieve 29 mpg's on the highway. I did it at sea level on flat terrain in normal mode without much difficulty. The LC had 20 inch OEM wheels and a crossbar but otherwise unmodified.

Below is a summary of information that may be useful if trying to maximize fuel economy.

Background
First, It helps to understand the design philosophy as described by Toyota because the I-Force Max 2.4L hybrid is different than traditional combinations of twin turbos, superchargers, hybrids, or AWD EVs. It uses a standard inline four cylinder turbo as the ICE, mated to a standard 8 speed transmission (less gear searching vs a 10 speed), and with an electric motor (EM) sandwiched in between.

This combination has produced the highest power, highest torque, and highest fuel economy ever in this class of its vehicles (LC and Taco). Other than the electric system, it leverages standard, well proven, and readily available light truck components for the engine, transmission, drive train, suspension, and brakes. It also has the promise of extending the longevity of the vehicle because it has fewer moving parts, and reduces the load on the ICE, transmission, and braking systems over its useful life. Only time will tell.

It is important to understand this architecture because in order to maximize performance the driving technique is counter intuitive. For fuel economy, it should be operated as a very low revving four cylinder vehicle rarely going above 2K RPMs. To do this, the driver must focus on leveraging the electric engine and induce its use as much as possible. Some call this "pulse and glide". Others describe it as driving by RPM vs MPH. Either way, the objective is use the electric engine more and the ICE less.

Driving tactics
1. The electric motor can sustain speeds up to 15mph on its own. RPM is zero and electric sound hums.
2. The EM can solely maintain speeds up to 30mph on its own. Once at speed, RPM drops to zero and electric sound hums. Soft pedal the accelerator so the ICE never kicks in.
3. The EM can sustain highway cruising speeds up to 65 mph while keeping RPMs within the peak torque 1700 to 1800 range using the pulse and glide technique. This gives rapid power delivery and forces the EM to provide the boost rather than revving the ICE or spooling the turbo. RPMs remain constant yet you feel the boost/pulse of the EM to push faster.
4. Just a note. Although not moving, I have noticed the vehicle can run the AC and other systems for a relatively long period of time while parked before the ICE kicks in temporarily and then shuts of automatically. This saves quit a bit of gas compared to other vehicles that must sit there and idle the whole time.

When people complain that they are driving 75 mph and getting lower than expected MPG it suggests they are thinking about it backwards. For those who would complain that it is too much trouble to think about and just want to drive the vehicle, remember that this philosophy will keep you constantly in the optimal power band (about 1800 RPMS) and provide the most rapid power delivery. In sport mode, it is a total blast.

By understanding how this very clever and capable system was designed and re-training your driving instincts it is amazing what can be achieved for both fuel economy and driving performance. I fully expect someone with a little time and practice can break the 30 mpg barrier soon.

Good luck

 

[Ike582]

I've hit 26mpg on two trips thus far. One was a 250 mile highway drive where I averaged 65-70 mph.

The second was an hour of bumper to bumper highway traffic heading to downtown Chicago. I was shocked by the high mpg on the second drive, until I realized that the LC was using only battery power for much of the trip. The engine was basically off and a light application of the gas pedal kept me in the crawl of traffic.

 

[RideWithYanu]

I have an anecdotal observation regarding the adaptive cruise control, distance spacing and a potential effect on MPGs.

I did a 2k out-and-back through the midwest a few weeks back. I used the adaptive cruise control for around 95% of the interstate driving. What I noticed is the distance setting regarding vehicle spacing seems to have an impact on MPGs.

At the ACCs maximum distance setting (4 blue bars) the LC held a more controlled speed while using almost no braking and minimal throttle to maintain speed. When traffic increased or I was passing through city centers I set the bars to 1 or 2 to decrease spacing between vehicles. While the ACC did an exceptional job at maintaining the distance, I noticed the brakes were being used quite a bit and then throttle/turbo was being applied to compensate for over correction. Multiply this brake/accelerate cycle by the tens to 100s over the course of a trip and I can see a mpg penalty adding up.

That’s a great observation, and it actually reflects what traffic engineers describe with terms like car-following theory, headway management, and the fundamental diagram of traffic flow. When cars follow too closely, small speed changes turn into waves of braking and accelerating that spread backward through traffic, a phenomenon called capacity drop. This doesn’t just hurt fuel economy but also makes congestion worse overall.

Put simply, leaving more space between you and the car ahead lets you drive more smoothly without constantly hitting the brakes or throttle. That saves fuel because your engine isn’t working overtime to keep adjusting. It also helps everyone else on the road by preventing the chain reaction of stop-and-go driving. Your anecdote about using adaptive cruise control on its widest setting is a perfect example of headway management working as intended. It’s not just better for your MPG but for the whole flow of traffic.

I’m not a traffic engineer, just a massive nerd who finds obscure topics like this one fascinating and research-worthy.

 

[GrayBeard]

Keep trying! It is definitely possible to achieve 29 mpg's on the highway. I did it at sea level on flat terrain in normal mode without much difficulty. The LC had 20 inch OEM wheels and a crossbar but otherwise unmodified.

Below is a summary of information that may be useful if trying to maximize fuel economy.

Background
First, It helps to understand the design philosophy as described by Toyota because the I-Force Max 2.4L hybrid is different than traditional combinations of twin turbos, superchargers, hybrids, or AWD EVs. It uses a standard inline four cylinder turbo as the ICE, mated to a standard 8 speed transmission (less gear searching vs a 10 speed), and with an electric motor (EM) sandwiched in between.

This combination has produced the highest power, highest torque, and highest fuel economy ever in this class of its vehicles (LC and Taco). Other than the electric system, it leverages standard, well proven, and readily available light truck components for the engine, transmission, drive train, suspension, and brakes. It also has the promise of extending the longevity of the vehicle because it has fewer moving parts, and reduces the load on the ICE, transmission, and braking systems over its useful life. Only time will tell.

It is important to understand this architecture because in order to maximize performance the driving technique is counter intuitive. For fuel economy, it should be operated as a very low revving four cylinder vehicle rarely going above 2K RPMs. To do this, the driver must focus on leveraging the electric engine and induce its use as much as possible. Some call this "pulse and glide". Others describe it as driving by RPM vs MPH. Either way, the objective is use the electric engine more and the ICE less.

Driving tactics
1. The electric motor can sustain speeds up to 15mph on its own. RPM is zero and electric sound hums.
2. The EM can solely maintain speeds up to 30mph on its own. Once at speed, RPM drops to zero and electric sound hums. Soft pedal the accelerator so the ICE never kicks in.
3. The EM can sustain highway cruising speeds up to 65 mph while keeping RPMs within the peak torque 1700 to 1800 range using the pulse and glide technique. This gives rapid power delivery and forces the EM to provide the boost rather than revving the ICE or spooling the turbo. RPMs remain constant yet you feel the boost/pulse of the EM to push faster.
4. Just a note. Although not moving, I have noticed the vehicle can run the AC and other systems for a relatively long period of time while parked before the ICE kicks in temporarily and then shuts of automatically. This saves quit a bit of gas compared to other vehicles that must sit there and idle the whole time.

When people complain that they are driving 75 mph and getting lower than expected MPG it suggests they are thinking about it backwards. For those who would complain that it is too much trouble to think about and just want to drive the vehicle, remember that this philosophy will keep you constantly in the optimal power band (about 1800 RPMS) and provide the most rapid power delivery. In sport mode, it is a total blast.

By understanding how this very clever and capable system was designed and re-training your driving instincts it is amazing what can be achieved for both fuel economy and driving performance. I fully expect someone with a little time and practice can break the 30 mpg barrier soon.

Good luck

View attachment 42537

I've observed this though you explain it better than I could.

As an example, my LC doesn't "like" the band between 45 and 50 MPH. I routinely find myself at or above 2K RPM if I accelerate into that band. But if I push through it and then back off to 50 MPH the revs drop and the fuel efficiency goes back up.

 

[mrCharlie]

I noticed MPG went down a little when I aired the tires down to the correct pressure (33 cold), from around 35-36. I just bumped them up to 34.5 trying to figure out a random cold-start Adjust Pressure issue, so I'll see if that makes any difference in MPG.

I've also noticed I lose a few MPG when I have the Kuat rack/mountain bike on the back, at least a bit more than I've noticed on other vehicles. Could just be that the MPG gauge is per trip and tank small so I see the impact more.

 

[pizzlegreet]

This is an interesting thread.

One thing that I have noticed is when I drive by those signs that tell you your speed it always says that I am driving a few mph’s slower than my speedometer. Also when I have Apple Maps or Google maps open, each app says that I am driving 5% slower that what my speedometer quotes. This makes me wonder if the MPG that is calculated by me LC250 is also 5% over.

I haven’t timed my odometer yet using the mile markers in the freeway but that’s next on my list of todos for checking this.

If the LC250 is in fact off then I am not getting the advertised mileage, changing my oil too soon, and running my odometer up. I’m in a lease so I will end up paying for extra mileage at lease end, etc.

My LC is stock—wheels, tires, everything.

 

[Midwest Duo]

This is an interesting thread.

One thing that I have noticed is when I drive by those signs that tell you your speed it always says that I am driving a few mph’s slower than my speedometer. Also when I have Apple Maps or Google maps open, each app says that I am driving 5% slower that what my speedometer quotes. This makes me wonder if the MPG that is calculated by me LC250 is also 5% over.

I haven’t timed my odometer yet using the mile markers in the freeway but that’s next on my list of todos for checking this.

If the LC250 is in fact off then I am not getting the advertised mileage, changing my oil too soon, and running my odometer up. I’m in a lease so I will end up paying for extra mileage at lease end, etc.

My LC is stock—wheels, tires, everything.

Time for a class action /s

 

[mrCharlie]

One thing that I have noticed is when I drive by those signs that tell you your speed it always says that I am driving a few mph’s slower than my speedometer. Also when I have Apple Maps or Google maps open, each app says that I am driving 5% slower that what my speedometer quotes. This makes me wonder if the MPG that is calculated by me LC250 is also 5% over.

I noticed this too when I had my 1958. My premium with 20s is usually just about in agreement. I saw 1-2 MPG better on the 1958 (calculated manually at fill up), which I attributed to skinnier tires and lower weight. I do actually care about MPG (to a point), so I feel a little better knowing I might not have lost efficiency in the real world.

Time for a class action /s

I know it was /s, but there have been various settlements over the years from automakers overstating MPG numbers. Most noteworthy off the top of my head, besides VW Dieselgate (which had a...few other factors) was Ford claiming 47mpg combined for their hybrids, which achieved 40mpg in the real world. These were more initiated by state/federal government versus class action though. I suspect our trucks fall under close enough.

 

[Rumbleandsway]

Increasingly believe the LC250 is what the Defender should have been.

We get the non-hybrid-diesel in Europe/South Africa and while it ain’t no Urus/Bentaga/RR [FF] it is so fit for purpose.

I get around 30mpg day to day with BFGKO2 & OEM roof bars.

Only thing I’d swap it for:

 

[teghogh]

This is an interesting thread.

One thing that I have noticed is when I drive by those signs that tell you your speed it always says that I am driving a few mph’s slower than my speedometer. Also when I have Apple Maps or Google maps open, each app says that I am driving 5% slower that what my speedometer quotes. This makes me wonder if the MPG that is calculated by me LC250 is also 5% over.

I haven’t timed my odometer yet using the mile markers in the freeway but that’s next on my list of todos for checking this.

If the LC250 is in fact off then I am not getting the advertised mileage, changing my oil too soon, and running my odometer up. I’m in a lease so I will end up paying for extra mileage at lease end, etc.

My LC is stock—wheels, tires, everything.

Mine was the same as well

 

[teghogh]

while I respect everyone’s input here I can assure you without shadow of a doubt if you think you are getting 29mpg on highway trips you are absolutely dreaming and are out of touch with reality.
I will put my money where my mouth is and will bet you 200 to prove me wrong
Go on a 100 mile round trip , use cruise control at 65 , fill up before and after and calculate the real mpg. You are most likely around 24mpg when all said and done .


Now as for the gx comparison, I live on top of a hill with 900 elevation and my country to work is 12 mile round trip going down to seal level all city streets with atleast 10 lights
My mileage on stock Landcruiser was 24 going down , when engine is warm , 19 going down while engine is cold , and 16-17 coming up
The modified mpg on the lightest 35s were 22 down warm, 14-15 up

On Lexus gx OT with stock wheel tire setup I get 20-21 down, 14-15 up .
There is no doubt in my mind that had the gx had stop start functionality it would match the lc mileage

The hwy mileage difference has been negligible in my experience as well. This maybe due to the gx having 2 extra gears
One other interesting point is the boost difference .
While the lc has no choice but to use boost going up my inclines the gx doesn’t use any at all. You have to go more than 40 percent deep on the gx throttle to see any sort of boost on the gauge.

 

[teghogh]

Well looks like Edmund’s also got the same exact mpg on both platforms after 200 miles and off-roading

 

[COSmurf]

while I respect everyone’s input here I can assure you without shadow of a doubt if you think you are getting 29mpg on highway trips you are absolutely dreaming and are out of touch with reality.
I will put my money where my mouth is and will bet you 200 to prove me wrong
Go on a 100 mile round trip , use cruise control at 65 , fill up before and after and calculate the real mpg. You are most likely around 24mpg when all said and done .


Now as for the gx comparison, I live on top of a hill with 900 elevation and my country to work is 12 mile round trip going down to seal level all city streets with atleast 10 lights
My mileage on stock Landcruiser was 24 going down , when engine is warm , 19 going down while engine is cold , and 16-17 coming up
The modified mpg on the lightest 35s were 22 down warm, 14-15 up

On Lexus gx OT with stock wheel tire setup I get 20-21 down, 14-15 up .
There is no doubt in my mind that had the gx had stop start functionality it would match the lc mileage

The hwy mileage difference has been negligible in my experience as well. This maybe due to the gx having 2 extra gears
One other interesting point is the boost difference .
While the lc has no choice but to use boost going up my inclines the gx doesn’t use any at all. You have to go more than 40 percent deep on the gx throttle to see any sort of boost on the gauge.

You are saying your LC on 35s (which given that dimension probably also means a heavy duty load rating) is capable of getting the same mileage as the GX OT on the factory issued OEM 33” SL rated Toyos… the ones with less tread depth and rolling resistance than that exact tire bought brand new from a tire store. That’s gotta be at least a 30 lbs difference in unsprung weight at every wheel. At LEAST. In which case the LC getting similar or same mileage is performing a heroic feat. Put heavy 35” tires on the GX with that much additional rotating mass and overcoming the extra 2” of diameter and see how the MPGs are then and how much boost the motor employs. My 5 days with the Tundra on 35s showed me plenty. It’s ugly… I couldn’t get an avg out of the 12s and that was a blend of city/highway. I’m positive if I was trying to hyper mile I could have gotten above 13 and probably even 14 if I did a lot more highway skewed driving vs an even split.

I agree that it’s unlikely for somebody to consistently get 29 MPGs on the highway in the LC on cruise control, especially since the cruise control constantly brakes to correct and maintain a set speed after accelerating. On a pancake flat highway and factory tires at the correct PSI, driving a steady 65 MPH will easily get one 25+ MPGs though.