I'm consistently getting between 19.5 and 22 mpg hand calculated and always fill to the top of the filler tube, 2025 P+. I have a light foot and this average is a mix of city and highway.
GX550 Real World MPG (1 Viewer)
- Thread starter supersix
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You're right. They really not comparable. I got the GX for greater towing capacity. Something very different.
With those mods, you're doing great!
In my first 299 miles - I’m seeing 17.2 mpg - mostly in Eco
My 2026 Overtrail here in Panama has almost 1500 kms, I wont use miles, cause my measurements are based on Japan testing.
Our daily commute is very different than usa´s and the rest of the world. Extremely short trips and horrible low speed traffic. Average daily speed of 30 kp/h based on every computer of my 4 different vehicles.
This Dude has an 80L fuel tank vs My 2022 Prado 150 87L fuel tank, so it starts loosing.
It´s new, and we haven´t done long trips to do a real highway test. Sadly we do not have highway, we have kinda interstate route were top speed is 80 kp/h for you guys is around 50 mph, yes thats the legal speed limit, there are less than 10 places in the whole country were speed limits are close to 100 kp/h or 62 mph.
Based on that my fuel economy is extremely different.
Duriing daily movements in city I´ve seen numbers that make me scared, between 20 to 25 L/100 kms , thats gives this dude a maximun possible range of 400 kms, which we never see cause the most i was able to fill this dude was 67L of fuel, leaving around 13 liters of reserve, very similar to the prado which i was able to leave only 12 liters of reserve.
Toyota is very cautios of this.
Now, this platform has the space to add a 30L fuel tank, seen already in the J250 land <cruiser prado 2.8 1GD ftv , the j300 land Cruiser F33A-FTV and V35A-FTS and the J310 lexux lx 600 V35A-FTS and Lx500D F33A-FTV. in total of 110L of fuel.
I do not understand the move of lexus by not giving this dude a bigger fuel tanks. It needs it.
For the time being the car has been filled up around 4 times + it was filled up at the dealer when it was delivered to us.
Best Fuel tank distance was 422 kms / 67L = 6.2 kms/L in the city + a little faster routes.
Japan data incity cicle fuel economy at 5.6 kms/L that is equivalent to 13.1 mpg in the city, on the highway japan data shows a 9.8 kms/L which in turn is 23mpg.
combined data in japan is 8.1 kms/L which is 19 mpg.
theoretical range of 448kms ( 278 miles) using 80L on city and 784 kms ( 487miles) on 80L.
noting that we on average do not use the full tank.
our tank is 80L or 21.1 gals ( Us Gallons)...
reports from u state 18 gals of usable tank .. 67-68 liters lets put a middle ground of 66Liters or 17.5 gals.
By calculations it means that our Gx550´s should be able to do:
City cyle 66L x 5.6 kms/L = 369 kms or 230 miles on city based on Japan numbers ( they do a more realistic fuel economy testing)
Highway cycle 66L x 9.8 kms/L =646.8 kms or 401 miles.
Worldwide Harmonized Light Vehicles Test Cycle (WLTC) in Japan – Japan Inspection Organization
That is their testing if anyone would like to read.
So any driving range that falls between 230 and 401 is great.
average in a perfect world should be 315.5 miles of driving range in a 50-50 cycle.
You can use all 21 gallons, just the same as your X5. Just drive the car until the gauge reads past empty before filling up.
The only difference is that BMW calibrates their fuel gauges so that "Empty" is truly about to run out of fuel, whereas Toyota calibrates their fuel gauges such that "Empty" means you're about to hit the fuel reserve.
You can tell by when the Fuel Reserve light comes on. In the BMW, it'll come on a little under 1/8 tank, whereas the GX's Fuel Reserve light will come on when you're basically sitting on E.
17.1 mpg over the last 2000 miles of mixed driving.
With 35 inch tires (Toyo Open Country C rated) and the Westcott lift, I’m getting 14.6 mpg combined.
18.6 mpg over the last 5k. Winter fuel and cold temps drop the mpg by 1-2 as well as short stop and go. Highway seems to be 20+ most of the time.. Driven rural town and back roads plus highway. Very limited city. I actually think it does pretty well for a full-time 4wd with power to spare in the shape of a box. Don't make the mpg complaints kill this great rig!
Something to keep in mind. If you move up to a taller tire, your MPG is actually a bit higher unless the odometer has been updated for the taller tire. My rough calculation is going from 265/70/18 (32.6" diameter) to 275/70/18 (33.2" diameter) increases your distance traveled by 1.84%. So if the calculation is 16 mpg, it would actually be closer to 16.3 mpg. If going from 265/70/18 (32.6" diameter) to 285/70/18 (33.7" diameter), the distance traveled increases by 3.4%. So if the calculation is 16 mpg, it would actually be closer to 16.54 mpg. Perhaps an engineer type out there can correct me if my numbers are wrong.
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Just returned from 2701.4 mile trip through the western states. Hand calc for fuel mileage (133.3 gallons burned) comes up with 20.27 MPG. This is with severe headwinds for almost the whole trip, including an absolute deluge going through Salt Lake City on the 27th. Even with the winds, we spent a great deal of time cruising at 80MPH through ID and UT. Ours is a 24 Premium+ and we just turned 13k miles on the trip. Love the GX! Something rather satisfying about setting the cruise on 80+...
26 OT, 275/70/18 no other mods in eco mode. I average about 17 +/- on roughly 50/50 street highway and I have a light foot trying to keep things smooth. I do encounter quite a bit of traffic, so when it’s open driving I can hit a pretty good number. I tried a one way commute early early morning and ended up 24 at one point. Not your typical though and that was on factory tires.
Did a 3000 mile trip from Wa state to San Diego. Avg 20-21.5 going down about 17.5-18.5 on the way back , headwind most of the way.
Have another Wa state to San Diego trip scheduled for Jun. running 275/50r-22 A/T tires.
Have another Wa state to San Diego trip scheduled for Jun. running 275/50r-22 A/T tires.
Good point about tire diameter affecting mpg on the odometer. I’m running a 35” diameter tire and my odometer states 14.6 mpg. My calculated mpg is really around 15.6 mpg. This makes me feel a little better.
I just did a 350+ mile trip up to a new job in Show Low, AZ. Climbed in elevation from my house at about 1400 feet to over 7,000 feet. Did about 20 miles off road as well, some in low range. I averaged mid-15s which surprised me (in a good way).
Keep in mind your bigger tires also affect the trip meter and the odometer itself, so if you're using those values to calculate MPG, you're sill probably underestimating a bit. You gotta use a GPS map or something like that.
📷 Lexus GX 550 Random Images
📷 Lexus GX 550 Random Images
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