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

[COSmurf]

Are you tracking actual gallons and miles on a spreadsheet? I drive like an old man, very easy and conservative.

I’m saying this very sincerely, if you are indeed driving very conservatively and smoothly and getting 17 MPGs on dead stock factory OEM setup, you might want to go get your car checked out. But if you have it lifted, with giant, heavy tires, and lots of body armor (sliders, skids) and roof rack, or like to pretty consistently draw on full power and acceleration, I would say that isn’t really worthy of complaining that you’ve been deceived if you’re averaging that with voluntary MPG killing modifications or driving style. Please share with us your setup so that we can help you troubleshoot.

 

[teghogh]

How is your mpg? I'm considering these. Are they actually 52lbs? Do you mind measuring the actual length of the contact width of the tire?

Good tire. Make sure you get the Goodyear wrangler rt that comes on 2025 broncos . They are much quieter and you can buy from ford dealer for 220

 

[TrailWhale]

It's entertaining watching all the new forum members have the exact same MPG discussion we've already hashed out 30 times already. It's like a rite of passage.

 

[Bad1975]

I'm on 255/80R17 All terrains (weight is equal to stock setup) Lifted 3" with heavier/beefier UCAs, have all Steel engine and transmission skids, Rago bumper including bull bar with winch, lights (16ft of 1/0 wire x2), Dissent rock sliders and few other smaller weight adders still average 22-23 without really even trying.

Worst I've seen is 21 MPG, except for offroad on two trips of ~185 miles each when I got 17-18 (for the whole trip with highway out and back) and as low as 12 MPG while climbing over 4700' multiple times, which quickly recovers on the descents.

The offroad MPG trips was quite impressive to me because the vehicle was fully loaded (4 people, recovery gear, chainsaw (26lbs.) cooler and a few guns. I had no free space in the rear cargo area except above rear seat level.

 

[EOD Guy]

Case in point, the MPG meter is not accurate. It you track actual miles and gallons from the pump on a spreadsheet, the results are not pretty.

Your point in this case is invalid............ While I didn't state specifically that I did the actual calculation, I in fact did. In my case the LC's MPG gauge and my spreadsheet calculation were extremely close, but not exact, hence my stating "ish". I do believe this is partially due to the fact that, it would be extremely rare to fill the LC's tank to the exact spot on every refill and not all fuel pumps are created equal and the pump(s) state's certification(s), while close, may or may not be exact and over time and many fill ups, any small percentage (plus or minus) would add up skewing the results of any "manual" calculation. Additionally tire size and or tire wear would also have a very small impact, but is still a variable.

Thus a true, accurate MPG calculation would only be possible if a known, measured amount of fuel was used in the calculation. But hey it's just my opinion, so my "ish" factor was reflected in my post.

 

[Sugarloafer80]

After a while when you own a vehicle, you get to know pretty closely how much additional fuel you can add after the initial pump shutdown to within a few tenths. That will get you within a few tenths in your calculations....consistently. It seems the fuel tank is on the left of LC. That would also suggest you would get slightly more in the tank if right side is higher. Would be pretty interesting if anyone has run the tank dry and done a complete fillup.

 

[COSmurf]

I'm on 255/80R17 All terrains (weight is equal to stock setup) Lifted 3" with heavier/beefier UCAs, have all Steel engine and transmission skids, Rago bumper including bull bar with winch, lights (16ft of 1/0 wire x2), Dissent rock sliders and few other smaller weight adders still average 22-23 without really even trying.

Worst I've seen is 21 MPG, except for offroad on two trips of ~185 miles each when I got 17-18 (for the whole trip with highway out and back) and as low as 12 MPG while climbing over 4700' multiple times, which quickly recovers on the descents.

The offroad MPG trips was quite impressive to me because the vehicle was fully loaded (4 people, recovery gear, chainsaw (26lbs.) cooler and a few guns. I had no free space in the rear cargo area except above rear seat level.

I only tend to mention my wheels/tires since that’s the most direct (and detrimental) variable I’ve voluntarily changed up, but I have a First Edition with all the extra aero drag and weight of the OEM roof rack, rock sliders, underbody skids, and mud flaps and still get very similar mileage as you have mentioned here with my heavy Load E all terrains.

I’m just stating this so others know despite me pointing out that lots of mods drastically reduce EPA estimates, like you, despite many gas mileage reducing mods, I get really good relative mileage.

I have no idea how people in 1958s or LCLCs with standard tire packages and no mods have been getting 17 or less MPGs unless they’re constantly dipping into full power and rapid acceleration.

 

[Sugarloafer80]

You students have radar for eyes?

Sadly many act as such, esp our drivers that spend too much time in traffic. It is very obvious as an instructor when a students latches on to the bumper in front of them.

 

[COSmurf]

After a while when you own a vehicle, you get to know pretty closely how much additional fuel you can add after the initial pump shutdown to within a few tenths. That will get you within a few tenths in your calculations....consistently. It seems the fuel tank is on the left of LC. That would also suggest you would get slightly more in the tank if right side is higher. Would be pretty interesting if anyone has run the tank dry and done a complete fillup.

In order the reduce yet another variable, when doing hand calcs I fill up the consecutive tanks at the same gas station. That way it’s more likely the pumps are calibrated more similarly or consistently. Even better if you can happen to fill at the literal exact pump you did the prior fill up.

 

[Mookie242]

With regular gas, I have averaged 25.7mpg in the summer and 20.9mpg in the winter. Very satisfied with the fuel economy and how fun it has been to be in 100% electric mode for good stretches.

 

[Gasherbrum]

Not to beat a dead horse, but my biggest variable in MPG is simply speed. At 65 mph, I was getting 27 mpg highway on the stock all-season's, right at the EPA estimate.

When I replaced the all-season's with AT tires it went down to just under 26 mpg highway. If I'm going 75mph my mpg drops to 22mpg, if you're going 80 I'm sure the drop is even more stark. Believe the EPA ratings are based on 62 mph, using premium fuel and stock tires.

Other item I noticed is that Eco mode seems to have virtually zero impact on fuel efficiency, so I always drive in normal. Given that the LC is a big boxy truck, I'm quite happy with the fuel efficiency.

 

[Sugarloafer80]

All most eco modes do is limit boost and deadening pedal response so only helpful for folks with less than ideal pedal skills.
And I also agree about the station consistency...a bit.
Most vehicles do get better mileage on premium if set up for it. The additional detergents help DI motors limit carbon buildup so in long run, you aren't helping yourself running cheap gas

 

[GrayBeard]

I'm on my second tank using ECO mode and am seeing a small increase in fuel efficiency. Though to your point, now that I know exactly where Toyota's programmed throttle response points are I'm going to switch back to Normal on my next tank and just see if I can match that with my own throttle control.

Watching the boost gauge I'm not sure if the LC ECO mode reduces it much if at all compared to what I'm used to in Normal. That being said, it feels like the shift points may be slightly different. I'm getting better performance in the mid-40 mph range in ECO.

I haven't read any tech manuals on this, so it could also just be me imagining a result I somewhat expected.

 

[PDPete]

That being said, it feels like the shift points may be slightly different

I wouldn't be surprised if it favors up-shifting earlier to keep RPMs lower... I know that the opposite is true when using Sport mode, the vehicle shifts later allowing the RPMs to rev higher.

 

[brian254]

I may have missed it while reading this very informative and entertaining thread, but is everyone factoring in how the nearly universal speedometer error—typically around 2–3%—can skew even hand-calculated MPG figures? If your vehicle's speedometer (and thus odometer) overstates the distance traveled, your MPG will appear higher than it actually is.

For context: my 2025 1958 edition, running Nitto Terra Grappler G3s in 285/70R18 (E load rating) and with the front air deflectors removed—but otherwise stock—is averaging about 18.5 mpg over the last 2,500 miles. By comparison, the first 600 miles on the stock 245/70 Yokohama street tires averaged about 20 mpg. These are the figures reported by the truck’s onboard computer. I did do a 1-tank test with hand-calculated MPG, and the result was within 0.2 mpg of the computer's estimate, so reasonably accurate—but still worth noting.

Just for comparison: I previously had a 2022 Lexus GX460. I never took it off-road and kept the stock street-tread tires. My average over a full year of ownership was 15 mpg. Since my driving habits or routes haven’t significantly changed, I think this helps illustrate how much more efficient the new Land Cruiser is compared to the older-design, naturally aspirated V8 in the Lexus.

Anyway, back to my main point—if your speedometer is off (as mine is, and as many other U.S.-market LC 250 owners have reported—just search for the many threads on the topic), your MPG numbers are likely a bit inflated regardless of whether they are computer-reported or hand-calculated.

 

[PDPete]

I did do a 1-tank test with hand-calculated MPG, and the result was within 0.2 mpg of the computer's estimate, so reasonably accurate—but still worth noting

Yup...If you're running the 1958 stock tires (31.5" IIRC), your odometer reading is likely artificially higher than actual miles traveled, and thus your MPG calculation will be higher that what it really is...if you're running tires larger than 32.5" (the stock size for base LC trim, and what I believe the North American 250s are all calibrated for), the opposite will be true. So unless you're able to get the "real" distance traveled from a source other than your odometer, it doesn't really matter if you're doing manual calculations or not.

If you're running the stock Michelins or other 265/70R18 tire (my assumption being that's what the vehicle is calibrated for), that should be pretty accurate, however.

 

[jayce]

What you describe would cause a measurement error of only 3%.

 

[brian254]

Yup...If you're running the 1958 stock tires (31.5" IIRC), your odometer reading is likely artificially higher than actual miles traveled, and thus your MPG calculation will be higher that what it really is...if you're running tires larger than 32.5" (the stock size for base LC trim, and what I believe the North American 250s are all calibrated for), the opposite will be true. So unless you're able to get the "real" distance traveled from a source other than your odometer, it doesn't really matter if you're doing manual calculations or not.

If you're running the stock Michelins or other 265/70R18 tire (my assumption being that's what the vehicle is calibrated for), that should be pretty accurate, however.

I never looked for a speedo error during the 600 miles that my LC 1958 rode on the factory 245/70R18s, so I don't know what it was before I upgraded to the 265/70R18 Nitto's. Nitto's specs say these Terra Grappler 3s are 32.64" tall. Since that is the stock size for LC LCs, I would expect my speedo to be close to 'dead on' if your theory were true.

All I can say is that with my 265/70R18 tires, Wyze and Apple Maps tested on 3 different iPhones all indicate about a 2.5%-3.0% error. So as with my earlier point, I suspect that my MPG numbers are about 2.5%-3.0% overstated.

 

[Sugarloafer80]

Back in the day, we used to do measured miles to see how accurate things were. Now with GPS, you can be very precise. 1 mile at 60mph should be 60 seconds. Run it, and see actual time. That will tell you the REAL error. Probably hard to do odometers because they calibrate in 10ths or a potential 10% error. I was told years back on many vehicles have vewry accurate odometers but they build in the speedo error. Auto company can't be held accountable for your ticket when you say you were doing more than gps would indicate.....but they can be on the other hand. Agsain I said it elesewhere, someone in the industry years ago told me they set the speedo based on max size OE tire they expected to be run on vehicle. have you ever had a speedo read low?? Of course not. Unless you go aftermarket and raise vehicle and add inches to the OD of the tires.
It was odd how they ran 245/70R18s on the 1958 with same sidewall of 18inch wheels v the 265/70R18 on the LC. Just a cost cutting measure

 

[Rijk Liebemshats]

If I take it easy I do 30+MPG (or 7.8 L/km as shown in the picture I took this morning). My LC is stock. I have no doubt that the average of 25MPG is easily achievable if you drive like a normal person and stay close to the speed limits.