Real World mpg

Once I finally found where the turbo boost and hybrid assist gauges were hidden on the 1958's driver display, I flipped back and forth between those and MPG crossing AZ with high winds. I noticed that with a headwind the engine was often into the boost and sitting there when I had cruise control on, which definitely contributed to lower-than-expected efficiency for straight highway miles at the speed limit. Didn't love that.
I was on I-10 East yesterday between Tucson and the AZ/NM border. Wind was fairly light. I varied speed a fair amount as it was all done with less than 500 miles on the LC. About 250 miles total before gassing up.
  • as you’d expect with aero drag increasing as the square of the speed you get much better MPG at lower highway speeds all else equal.
  • in adaptive cruise at 65 mph, MPG about 22.5, in adaptive cruise at 80 mph, MPG about 18.5
  • adaptive cruise with LDA (land departure assist) on then the LC pretty much drives itself. I’m not interested in self driving but it really enhanced safety.
  • forward driver monitor camera is somewhat annoying but I may keep it
  • I was most surprised by fuel left in tank before fill-up. My screen said 50 mile range left but I added only 13 gallons with meter just below 1/4. So about 5 gallons was still in the tank an excellent reserve of about 2.5 or so gallons.
 
It’s there.
-Scroll all the way to the right in the DID,
- Select the picture of the two dials with the gear on it.
-Scroll down to the leaf image & select
  • Select Fuel Economy
  • Select ‘Tank Average’. It will reset at each fill-up

So I did more menu diving today, and have come to a conspiracy theory level conclusion - the tank average is only available on the 1958 trim. It looks like you have a 1958, and the driver information screen is a little different on that. I have the LC trim and I legitimately can only find the option to choose between trip and total average. 👀
 
I'm aware many are coming from V8's and V6's with much more power. I'm not. I drove VW 4-cyl 5-spd TDI Diesels for 20 years of my working career ~110 mile R/T commute, before I stepped up and bought a Grand Cherokee Eco-Diesel in 2016. What I can say about the 4-cyl diesels, is that no matter how hard you pushed them (85-90MPH), the fuel economy rarely suffered. I have hundreds of spreadsheet logs from my weekly fuel purchases showing my fuel economy was routinely 44-46MPG at those speeds. A gasser 4-cyl, on the other hand, does not have the capability to continually deliver fuel economy at 80-90 MPH. Especially in such a large, heavy vehicle. In other words, I think 24MPG is attainable without a roof rack and keeping the speedometer under 65.
I have the same experience as you with my 2020 GTI which is a turbo 4 cylinder gas. The reason the mileage seems to vary less at higher speeds in these cars is not due to the fuel source (gas vs. diesel). The physics is the same for both, the engine is doing work pushing the car through the air. The total aerodynamic force on the vehicle is proportional to the product of the aero drag coefficient and the square of the relative speed of the vehicle with respect to the air. (No wind this is just the vehicle speed). For a sleek and small car like the VW or Camry the aero drag coefficient is much smaller than for the LC. I’d guess the Camry has a drag coefficient 1/3 that of the LC. The LC is a brick for sure. Therefore at all speeds the aero drag is much less in the Camry than the LC. On level ground the drivetrain must overcome this aero force together with the tire and drivetrain drag; it is a bigger net effect on the LC when comparing over the same roads/speeds.

If you carefully looked at the data in your spreadsheets, I believe you could verify a nearly linear relationship between MPG and the square of your average speed.
 
So I did more menu diving today, and have come to a conspiracy theory level conclusion - the tank average is only available on the 1958 trim. It looks like you have a 1958, and the driver information screen is a little different on that. I have the LC trim and I legitimately can only find the option to choose between trip and total average. 👀
Yes, you are correct 1958. I bought it and really like it but will likely sell it next year (or give it to my son) and get either the 2025 LC or the 2025 GX550 Overtrail. I also want to look t the 2025 4Runner.
 
Anyone knows the mpg difference between 20 vs 18 inch wheels?
 
Just completed a ~600 mile trip from Portland OR to Oakland CA. Mostly 75mph using cruise control. Premium fuel. Average for the trip was 22.8mpg; I was hoping for 23, so I can count this as "close enough" to satisfy me.

EDIT: forgot to mention I was in "Normal" Drive mode. Would "Eco" have moved the needle much?
 
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Picked it up today. Reset everything. Got 25mpg on the highway on the way home, and 22.6mpg driving around city roads. Pretty darn happy with that! That’s the same as my compact Mazda CX-30 crossover (with Turbo).
 
Been working on hypermiling, I’m not sure what everyone is talking about, my mileage is amazing. /s
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I’ve been reading the posts in this thread with anticipation of getting good milage on my LC FE when I pick it up from the dealer on Monday, four days from now.

Strolling through YouTube the other day, a video from the Car Care Nut showed up.. I wonder how many of the reports of dismal fuel economy involved driving in a way different from what he describes in this 19+ minute video?

 
I've got about 500 miles. 50/50 highway and city in Northern VA. Averaging about 22 while notnin eco mode and not particularly gentle on the throttle. I have no idea how some are getting 19 or less
 
Just did my first fill up.
Pump average was 22.7 (333 miles driven / 14.7 gallons).
Not bad i would say as was 99% city/commute driving and a couple short backroads trips.
99% on normal. Tried the sport mode a couple times and same for Eco mode.
Sales man reported that he filled the tank originally with premium.

Interesting that I still had 20 or so miles left on the dash, however no gas tank light came up.
Next tank I'll try to push it down to 0 as by my calculations still 3 gallons left with 60 miles range (@20mpg), discounting the 20 on the dash that gives 40 miles after the dash gets to zero...
 
I currently have 1200 miles premium gas . 300 plus mile 99 % highway at 75 mph cruise 17.5 mph, fully loaded with stuff and surf board on top rack .Eco mode
2 adults and 2 kids
 
I picked up my Trail Dust LC trim level on Saturday in Las Vegas, then drove the 190 miles home to Cedar City. Without a gauge reset to wipe out all of the time the LC was running at the port and dealership, I got 19.4 MPG for that first tank.

This morning, after resetting the gauge, I took it out to my local hiking trailhead and back, 21 miles of mixed driving. I got 23.9 mpg so am pretty happy.
 

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I’ve got a FE. Mileage on stock tires, reset and first rank of gas was 23 combined. Put on some Falken AT4W’s and getting 21.1 combined. I’ll take it.
 
I have another thought... Shocking... I know

I have been kinda bummed that I'm only getting about 18MPG with my new LC with less than 200 miles on it... Then it hit me!

I'm driving in 116 degree heat with a car that uses the hybrid battery to run the Air conditioner!

With this heat... the A/C has to be in overdrive... sucking the power and making the engine run.. way more... than if it was only 80 degrees

So... What affect does running the A/C or Heat in extreme enviroments have on MPG?

You guys getting 22 + MPG... What is your ambient temp?

You guys getting 18 MPG if your lucky... What is your ambient temp?

It's got to be a factor... The issue is how much... if any?
 
You guys getting 22 + MPG... What is your ambient temp?
MIss Daisy is getting 23- 24 mpg on two lane country roads doing 45 to 60 mph, in the 85°-95° humid south. I will go faster when out of the break in period.
 
I have another thought... Shocking... I know

I have been kinda bummed that I'm only getting about 18MPG with my new LC with less than 200 miles on it... Then it hit me!

I'm driving in 116 degree heat with a car that uses the hybrid battery to run the Air conditioner!

With this heat... the A/C has to be in overdrive... sucking the power and making the engine run.. way more... than if it was only 80 degrees

So... What affect does running the A/C or Heat in extreme enviroments have on MPG?

You guys getting 22 + MPG... What is your ambient temp?

You guys getting 18 MPG if your lucky... What is your ambient temp?

It's got to be a factor... The issue is how much... if any?
I'm in Vegas and it's been like 115-120 for most of July. Even then I'm still getting 23-24MPG. Currently 24.1 at 923 miles.
 
I don't have any data to back this up, but I imagine running AC saps around 1 MPG. If both front and rear AC are running, around 2 MPG.
 
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