2018 Tundra gas range keeps getting lower.

since i have had this 2018, a full tank of gas will say that i have 424+ miles till empty. i would say over the last 4-5 fill ups, the range has been dropping each time. i was at half tank this morning and filled up, which is roughly 16 gallons and started the truck back up and now the range is at 389 .

truck has 48145 miles.

 

The ecu learns and adjusts to how you drive. Unplug the battery for 15 min and it will say close to 600 DTE again at first. But it will drop again as you drive it.

 

hmm. interesting. i would think that the mileage would go up as i am driving less miles to work . went from 36 miles round trip to 16

 

Agree on Avg.. Driving habits, throttle response, City/Hwy conditions, stop and go traffic, load bearing, etc are factors on avg fuel mileage... Still a great truck!! Good luck

 

i have noticed that it is not accurate.....but this is a huge drop from what it used to be.

a great truck that is for sure.

i would say that with the shorter drive to work from where we used to live...i dont have the stop and go, faster speeds that i used to have. i know i used to get on it more , but dont really have to now as there isnt much traffic on the way to work.

 

Vehicles are most efficient in their warm operating range. Short trips usually mean cold trips, and that'll tank the mileage.

 

define warm operating range. the truck is warmed up until the temperature gauge is off of cold.

 

The idle hammers the number as well. It's kind of a catch 22, but know that if you warm it up and stretch its legs on a longer run you'll get better than the computer tells you as a result.

 

If you’re doing this more recently (as I do when the temp drops a little at night), that’s however many minutes of driveway warmup at 0mpg’s.. just some $.02

hand calculate is the way to go if you’re really concerned about it. I trust my gauges and use the MTE as a guesstimate and fill up between ¼-½ tank.

 

i have always warmed up the vehicle since having it....and did the same with all my other ones i have had in the past.

i fill up at around half a tank as with the current prices going up, filling up at 1/4 is going to be a mortgage payment.

 

on the way to work, i think the speed limit is 55 or so and i do around 60+.....and that is for 5-6 miles and then its a few side streets where the speed limit is 30

 

Gotcha. Again, as most have suggested, the MTE calculator is very dynamic and more often than not, incorrect.


Hahaha yeah. This is about the only time I’ve enjoyed my 26gal tank.

 

totally agree.

 

Not totally unrelated, but I have friends who sit and finish a phone call in their car or truck before shutting the engine off when they get to where we work, sometimes for 15 minutes or more. Sometimes they run and grab lunch and sit and idle for an hour while they eat in their vehicles and listen to a podcast.

When your truck is running and you’re not moving, you’re getting 0 mpg and that is being factored into that average readout on the dash. And burning fuel without moving gives you fewer miles to empty. Only one guy I know who does this actually complains of his 4Runner’s fuel economy. It’s a ‘98 with 400k miles.

 

@Terndrerrr

that would make sense, but the truck is started a few minutes before i leave for work and might be running for 5-10 minutes before i come out and then leave. i have been doing this since i bought the truck from day one....and mileage was always in the 430+ range up until we did this move , which was almost 3 months ago.

 

The only way you'll ever get more than an approximation is to check it yourself. Divide the actual miles driven by the actual gallons it took to fill up. It'll never be exactly the same, but you should be able to explain why it varies much from the norm -- lots of highway would increase mpg, lots of city would decrease it, towing a 6000 trailer would decrease it a lot, towing the trailer into a headwind -- Lord have mercy!

I'm sort of anal about it myself. I keep a spreadsheet on most of my vehicles *, and I write the odometer on gas receipts. When I get home I post the date, odometer, fuel amount, and dollar amount to the spreadsheet, and it tells me the MPG. It's often up to a full mpg less than the average for the tank on the truck. I also use the spreadsheet to keep up with maintenance, so it's not a total waste of time.


* not the ZRX. It's a hot rod pure and simple.

 

It’s just like this. I’m not sure if your 16 mile drive is stop and go or highway speeds, but it’s harder to get the truck from 0-55mph than to maintain 55mph. If you did another 20 miles steady at 55mph, you’d raise your mileage. Also like others said about idling. My mileage sucks in the winter because remote start my truck and it gets 0mph for 10 min before I leave. I’ve seen some cars won’t calculate idling, but the tundra does.

 

Time for an oil change

 

I never understood this. You fill up sooner and more often, but at the end of the day gallons is gallons and the current price is what it is. It may be less sting being 50 bucks to fill up at a half tank, but 50 bucks every few days to a week to top off, vs, filling up when empty....when you're still the same amount of gallons. 50 bucks on Wednesday, 50 bucks on Sunday is 100 bucks a week. Fill up once a week.....still a 100 bucks

 

There are a few reasons to keep the tank in the upper half

• A tank with less fuel in it is more likely to have condensation, so keeping it in the upper half is better for this.
• With fluctuations in fuel prices if you head to the station and don't like the price, at a half tank you have the option of holding out to see if the prices go down in a day, two, or even a week. If you're running low you may not have that option.
• Purely the psychological comfort of not having a triple digit fill up.

You're not wrong that a $100 in fuel is the same whether put in all at once or in two separate payments. The only time it might bite you would be if some world event were to spike the prices for a week when you needed to top up and you couldn't wait it out.

 

When was the air filter last changed?

 

Didn't see it mentioned but winter gas will also drop your range to empty.

 

I let 'er rip the other day at a stop light and lost .1 mpg

Shrug, it was worth it.

 

So will colder temps. Are the MPGs reading lower? Are you resetting the MPG on each fill up?

 

The truck automatically tracks MPGs per fill up, so no resetting is needed if you want that info. I don't do anything special. I buy the fuel, and drive the truck. If I'm not on a schedule I'll cruise at 65 if I want to get better mileage, but I don't fret over it in general. I have run the numbers manually enough that my dash computer is accurate enough (within 0.1 or 0.2 MPGs usually) so I have the info if I need it.

 

You’re also keeping more weight on the truck by continually topping off your tank. As ridiculous as it is, I can tell a difference in how my truck handles when I have a quarter tank vs full. I just drive till empty and fill up.

 

True for miles per tank but MPGs are cumulative.

 

Beat me to it. I don’t know where OP lives but up here in Maine I lose a few mpg in winter. Its expected, more dense air, more drag, combustion stuff, science, blah blah.

 

In the dash LCD there is a screen for MPG average per tank. I see your truck is a 2017, so it might have been added in the later trucks. If you'd like I can get a pic of the screen for you, but it does per tank MPG.