MPG Question….

I have a 2025 TRD Sport with 18”. I was getting around 23.5 MPG. I put an AFE Air Filer on it, getting around 24.5 now. Guy I work with has a 2025 SR5 (4x4) with 17” tires. He’s getting around 26 MPG. Just curious if others are getting better MPG. All in I’m very pleased with 23-24 MPG considering I have 18” tires along with it being a 4x4.

 

Be easy on the accelerator, go slow when accelerating, make sure to watch your RPMs while doing so. Also I think that truck has an eco mode? (Not sure, anyone correct me if I'm wrong) Additionally just slow down, don't go faster than nessecary.

 

My basic 2025 SR5 4x4 with 17" is showing mostly 27.3 mpg on its own calculator over the last 2,000 miles or so. Note that it's mostly highway driving at <70 mph, and once I learned that the truck was observing my driving style I got a very light foot.

It's got a bit over 3K miles on it now. When it was brand-new I drove it home to MI from VT via upper NY and Canada. In Canada on the 401 and 407, every Canadian with a driver's license was driving between 80 and 90 mph and pretty soon I got with the program and was howling along, staying under 90. The truck calculated over 23 mpg even under those conditions.

As stated , I live in MI, and in a few months frozen white stuff will be covering our roads and we'll be plowing snow with our tires (and maybe with that front air dam). That will hurt the mpg. I've still got my old 2005 Ranger, my old friend, and that may do ordinary duty in the winter--runs to the grocery store, work commutes when the city hasn't plowed yet and I can't ride the bicycle. But the Tacoma with 4WD, my first ever running on all 4, will be called out when the going gets tough.

 

I just discovered that my new truck gives me a "this trip" readout at the end of every drive. I just did a 10-mile trip (each way) that I'd describe as suburban-urban. On the way in the readout said 23.4 mpg. On the way back, 30.0. Slight difference in routes, red lights,and stop signs. My 145 mi. highway trip here last night rated 28.3 mpg.

 

Don't trust the data you're getting from the truck. It's almost always optimistic. Hand calculate fuel mileage and compare it to what the truck says. Some vehicles will be within 1 mpg. Others will be off by 3-5 mpg. But the numbers on the dash will always be better than you're really getting.

After you've done enough by hand you'll have an idea. My F150 was never off by more than 1 mpg and usually closer to 1/2 MPG. But the Explorer my wife drives is usually 2-3 mpg higher than hand calculations show. We used to have a Honda that was 3-4 mpg high. My Chevy Colorado has been off .7 mpg on every tank so far.

18" wheels has nothing to do with it. It's the tire size. You can get tires exactly the same width and height and mount them on 15", 16". 17", 18" or 20" wheels. The only difference is the size of the hole in the middle and how much rubber is between the ground and the bottom of the wheel. Smaller wheels mean more rubber, a softer ride and they work better off road because the tire can flex more. A larger diameter wheel means less rubber between the ground and bottom of the wheel. That means a stiffer, firmer ride, but they also are more stable when driving aggressively on pavement.

 

I put sport 18 inch wheels on my SR5 and lost a mile a gallon or two, even compensating for the larger tire size.

 

I am getting 17.3 according to the truck... But thats with a lift, E rated all terrains, engine and trans skid plate, and a roof rack. Depending on driving conditions ill safely get 300 miles on a tank, which is good enough for me. I tend not to think deeper than that.

For what its worth, when it was bone stock, i was only getting 18 average driving it without my foot in it.

 

About 1,800 on the odometer. 17.8 MPG. I get ethanol free at QT, it's either 90-91 octane. 6-speed. Little to no highway driving.

Maybe someone has a spreadsheet with categories? I would be interested to see what difference octane, in-town, manual, etc. have.

And I'm okay with the 17.8. My foot is in it and it's a big truck.

 

The very best way to calculate fuel economy is to log your odometer and fuel usage every time you fill up. Granted, this only gives you an average overall fuel economy. But if your driving patterns are fairly regular, it is the best way IMHO. All it takes is a 3x5 card and a pencil. And a minute. Although there are apps you can use on your phone.

------------------------

Miles Elapsed Between Fill-ups (miles) / Fuel Used Since Last Fill Up (gallons) = Overall Average Fuel mileage (mpg)

-------
1) You have to start with a refueling event. No matter your current mileage. Whatever is on your odometer. Re-fill your tank to full. Once the pump shuts off. You are done. No topping off. Write down the current odometer reading --> such as 12,345 miles on your 3x5 card that you toss back in the glovebox or fold into your wallet.

2) Drive normally, just like you always do, and refuel like when you always do. Say typically around 1/8 tank remaining, maybe a week later.

3) Refuel again. For the most accurate overall mileage calculation, refuel at the exact same pump you did last time. Or at least the same station and definitely the same octane.
Fill the tank just like last time until the pump shuts off. No topping off. Once the pump clicks, you are done.

4) Record the fuel volume you just put in your tank. Say 14.2 gallons.
Record the new current odometer reading. Say, it is 12,605 miles now.

>>>> These are hypothetical numbers. Your numbers will vary. But this is the best overall technique. This is the technique I use.<<<<

So you have driven 260 miles since the last fill up. [12,605 - 12,345 = 260 miles elapsed]

And you took on 14.2 gallons of fuel. Presto --> Your overall fuel mileage is 18.3 MPG [260 miles elapsed / 14.2 gallons used] = 18.3 mpg on average

-------------------

See how this compares to your dash computer, assuming you reset your trip odometer and MPG the last time you filled up. Hopefully, they agree with in reason. But the derived method above is by far the more accurate measure of overall MPG than whatever is displayed on your dash.

Monitor over time. Fluctuations between 0.1 to 1 MPG per fill up are perfectly normal. Ambient weather conditions like cooling off in fall will make a difference. Taking a long trip on the freeway will make a difference. Spending a week at commuting to a different way to work due to construction will make a difference. Increased traffic since school started will make a difference.

Trending or tracking your MPG over time can be useful in determining if maintenance or other corrective action is required. Obsessing over very small differences in MPG from tank-to-tank is an exercise in futility IMHO.

 

The fuelly app is my go to. The 2024 OR I have average mpg is 17.4. The heavy KO3 tires are a significant factor.

 

I've kept fuel records since getting my Datsun 510 wagon in 1980. Every drop gets recorded wth date, amount, cost, and odometer mileage. The calulations can be quite accurate as the records accumulate. I even keep records for the '61 Chevy since the engine rebuild, mostly for amusement: "You mean we tolerated lousy mileage like that back then?"

 

It's the tire/wheel weight and size combo. My '24 SR5 with the factory garbage 245 Firestones the gauge would show 25-26 quite frequently. When I went to an all terrain 265's I struggle to get 21 some times now. But, I'd rather have better traction in crappy weather than higher MPG's. If I need MPG's I'll take one of the cars.

 

There are now about 50 MPG threads. Guys are getting 15-31 for the hyper milers. Everything is going to vary what one gets for MPG.