Fuel Range question

Something similar has been happening to me for the past 5 fill ups or so. I used to get around 318-328 miles until empty and now for them past 5-6 or 6 fill ups I’m getting around 290 miles until empty on the odometer.
I have a 2019 TRD off road with Kings suspension and 285 70 17 BFG all terrain. Any feedback would also help me understand why.

 

Going above 70 mph kills the mpg. Yesterday I did 325 miles highway, 67-78mph and averaged 18.8 mpg, with 265 75 16 wildpeaks and scs ray10s with - 12 offset, so that also hurts my mpg. Next week im lifting 2 inches so I'm gonna take another hit.

 

Plus winter blend fuel sucks ass

 

I figured it out. The bigger tires are what’s killing it. The previous owner of mine had tires that were way too big for it. I have 275/65 KO2’s on it now. I was midway between 3/4 and full tank and had 208 miles to empty. I reset the ECU and then it shot up to 312. I’m pretty sure I’ve fixed it.

 

Big heavy tires take alot more gas.

 

I haven't had the opportunity for that type of a distance on highway, but I think being easy on both pedals is the key. Every time you tap the brakes, you'll have to burn some fuel to make it up. Driving defensively and with minimal speed changes makes a huge difference. I bet my Tacoma gets better mileage than the Civic weaving in an out of traffic, riding up on someone, slamming on the brakes, going 40-70 every two minutes.

 

Probably not. Lol. I have a scion tc and beating shit out of it I still got mid 20s

 

That's not bad. A lot better than I'd assume. I was always curious because it's not my driving style and I never really beat on a car too badly.

 

I had a 2017 OR that always said 385 miles to empty after a fill up. It got totaled in a wreck and i replaced it with a 2019 OR. Now, every time I fill up, the mileage says something like 320 miles to fill up. My average mpg has always been 18-20 with both. So, what changed?

 

How did you reset the ecu? Battery disconnect?

 

My 2019 Taco does, but only when using the radar cruise control. If i hold the button to engage manual cruise it won’t

 

My 2017 always said 385. My 2020 says 345.

 

Update and conclusion. After resetting the ecu, my Taco looks to have a fuel range of 416. Which is a hell of a lot better than the 260ish I was previously getting. These Tacos really have a lot of weird quirky “issues” with them. Now on to the “axel wrap”..........

 

Yes. Unplugged the negative battery cable for 20 minutes then plug it back in.

 

I'm in Oklahoma as well and I believe the computer says around 280 mile range on a fill up. I have lift, wheels, 285/75R16 E rated tires, steel front bumper with winch, roof rack and diamondback bed cover. Computer says I average 14 mpg and I drive "like an old man" (according to the wife). I've never done the math to find out what I am truly getting.

 

I would think it’s the tires as well as the extra weight. But especially the tires. That’s the exact size mine had on it when I got it. It has smaller ones now.

 

I bet. Computer said I was getting 18 mpg prior to any of the mods. Going to fill it up, keep track of mileage and fill back up and see what actual mpg is. Compared to the computer reading.

Just dropped it off for its first service. I’ve read that ppl say the mpg goes up as it get broken in. We’ll see.

At the end of the day, it is what it is. I didn’t buy the truck or do the mods with mpg’s in mind. Bought it because they are super reliable and I feel like they are the best looking trucks on the road. Personal opinion of course.

 

***
Not always but yes in general. Denser air = more fuel. So, if that is the case, why is everybody chasing CAI??? Wouldnt HOT air lower gas consumption?

 

Exactly! I bought mine to rig up for over landing. I still have lots to mod. But the short fuel range scared me at first. I didn’t want to mod it and the range just keep going down from 260... That’s why I chased this and was ultimately without knowledge of these issues.

 

My mpg has gotten no better, I'm at almost 9k miles now.