Well, convince me otherwise..

Buys a full sized pick up expects MPG's of a small sedan...

Please, people please stop with the gas mileage thing. its a 5.7l gas v8 in a 7000lb truck I'm not sure if you actually believe the mpg ratings car companies pass off but if you are worried you should have bought a different vehicle.

that being said OP not sure what your other uses are for your truck, but seems silly to loose $ on the deal just to gain a few MPG

if so, regear, air up the tires to 60++ psi and get a bed cover to help with air flow those things will help some. maybe 1-2mpg at best..

 

You bought a Full size Truck with a V8 that produces nearly 400hp and expected "good" gas mileage?

If you want full size truck and good gas mileage, I recommend the F-150 with the 2.7L Ecoboost. My brother owns one and regularly gets 19-21mpg.

 

When buying it, you shouldn't have to "expect" good gas mileage. It's on the website and posted on the vehicles:



So not sure why it's a "surprise" that we get less that 15 MPG

 

You need a electric motor swap

 

At the end of the day, OP, you gotta do what's right for you.

At times, I wonder about getting something more fuel efficient... usually though, that's followed by some situation where I'm so thankful i have a full size truck. This week it was in hurricane prep. I've no idea how the fuck some of these people made it home with plywood on the roof of their car, held on with twine or laid askew in their micro truck bed... I laughed at the guys trying to throw a 200lb generator in the back seat of an accord... (it didn't fit)

But that one instance this year reminds me that I don't give a crap about 13mpg... A rock solid reliable fullsize truck bed is a pretty nice insurance plan for when shit gets weird, shitty fuel economy is a small price to pay, at least in my opinion.

But.. as i said at the start, you gotta do you.

 

Lets get something straight here, i'm not new to the Tundra world. I've owned a 2007, 2014 and now a 2018 all of which I purchased new. I know from the past that they get 13-15 mpg at best, I'm not trying to get sedan mileage here, if I was I be driving my wifes 2018 Chevrolet Traverse which gets 30 mpg. I guess what most have failed to comprehend here is that I stated that in the beginning I was getting between 19.5 and 21 mpg on the highway driving back and forth to work, I don't give a shit about the city mileage as I know most vehicles drop significantly while driving in town. My concern/question is why the huge change in mileage? I'm down to 13.6 to sometimes I hit 17. Is it the difference in the outside temp? the relative humidity, is the truck "learning" just want a good ol' college effort here as to why the big difference in mileage since I purchased it new July 13th, 2018 with 7 miles on it.

 

Some of the replies here are the reason Toyota has not updated, significantly, the 5.7l.

The "you bought a full size..." the "nearly 400hp" and the "If you wanted maybe..."

Those were all legitimate responses in 2007 when it made more power and got at least equal MPGas its competitors. But where I live, in 2018, the near 400hp is normal, the other trucks weight more, many tow more, have box frames, true LSD, and even better paint, its time to bring the engine into this decade.
NO ONE can argue the reliability factor, Tundra trumps that category. No one comes close on interior room, last I checked, and of course, that body!

To the OP - I too saw a drop in what was my pen and paper MPG about 10k miles into ownership (although it was used). From the hundreds of threads I read, regardless of age/miles, things like checking simple maintenance items and fuel source can be key. You stated you use the same gas from the same station. Change it up.
My experience over 10years of and driving Nissan Z cars, I found dependent on my choice of fuel, played a roll in MPG and dyno numbers.

Mike

 

I just traded in a 2018 Tacoma TRD Offroad 4x4 for a 2018 Tundra Limited 4x4... so here is my comparison:

Tacoma upsides
Averaged 19.6MPG over 19,300 miles with 275/70/17 Toyo AT2 with no lift and probably 75% highway driving
Tech package and Premium Package make the equivalent of a Limited while maintaining real off-road use
Perfect size to go off-road and CRAWL is a great option to have for that one time you use it
Parking is so easy!!!! Its a great size exterior wise
Residual value

Tacoma downsides
Bed is not very large and losing the space over the rear wheel wells makes it kind of narrow
Rear seats are ok but if you have anyone around 6' tall they'll want to drive on their own
Rearview mirror gets in the way of cross traffic and/or pedestrians crossing the street, you need to look down and around to clear
Tailgate is heavy as heck for a small truck... feels at least 2x the weight of the Tundra tailgate
Bed feels very flimsy... I leaned over the side of a bed a few times to get/put something from the bed and felt the sides flex and pop back out
Transmission gear hunts a lot which you can work around by having in S mode

Overall, I really did enjoy my Tacoma. Its a great vehicle, no wonder Toyota sells so many of them. If the Tacoma would have had 6" more of space in the backseat, I wouldn't have traded up.