[Instrument53]

2015 Crewmax with 4.6. Use it for business and they are now changing how we are compensated for our vehicle and gas. So I have a few questions that I hope can shed some light. When I fill up, it shows how many miles till I'm empty. How come that number erodes a lot faster that my gas needle?? It seems like after about 10 actual miles that number shows maybe a difference of 14 to 15 miles. Also, has anyone notice a difference in consumption, say between driving 60 mph vs 70 mph? I notice that there is very small difference in RPM when I vary from 60 to 70. I am going from a gas card to compensated to 21.3 cents per mile. When I had the gas card I got use to driving at 70 and now I have to back off the go pedal.

 

[IamRay]

Miles til empty: My 2015 5.7L will display 325-340 miles to empty on a full tank during the summer. That number can drop to 290 in the winter. I figured it was gasoline formulation changes between summer and winter. However, the number shown usually tracks pretty close to how far I go between fill ups. For example, if I fill up and get a "Miles to empty" reading of 320 miles, I can reset my trip odometer and will be getting fuel in about 320 miles.

My fuel gauge runs to empty as the miles to empty approaches 0.

My fill-up is about 19.5 to 20 gallons when my "mile to empty" reading drops below 10 miles remaining. I don't count the 6.5 to 7 gallon "reserve" that remains.

As for mileage difference between 60mph and 70 mph...my first gen Tundra (with 4.7L) was very sensitive to speed increases. I usually could get about 16.5 mpg at a steady 60 mph; I once got 20 mpg under perfect conditions going cross-country with the cruise set at 60. At 70, that mileage usually dropped to mid-15's and below 15 at 75. My 2015 5.7L is somewhat less sensitive, but I can still see a drop of about 0.7 mpg between 60 and 70.

21.3 cents per mile seems pretty chintzy for mileage if you're using your private vehicle to conduct company business. Even if you had an economy car, I'm not sure 21.3 cents would cover your total cost of operating the vehicle on a per mile basis (fuel, maintenance, insurance, depreciation, taxes and tags........)

 

[OldGuy43]

You put your full trust in any "distance to empty" indicator at your peril. When using it, you should think of it of a constantly updating "idiot light" that becomes ever more important as the tank level falls. The large reserve of the Tundra will protect most fools who will trust the accuracy.

I quit betting on the accuracy of "distance to empty" meters when I was left out-of-gas on the I-10 exit ramp to West I-620 Loop at rush hour in Houston, Texas. NOT a Toyota. (Some of most intimate details of your vehicle you have to learn through bad experience.) The nearest convenience store I found was maybe four miles away, and then I had to buy a gallon of milk and pour it out just to take a gallon of gasoline back. :051::banghead:

Oh, yeah, I had to leave my nervous wife with the car. I got back to find her with the family 40S&W on her lap. It seems a van of scroungy characters had stopped to "help her", but left after she explained everything was under control.

 

[IamRay]

I only started using or relying on the "Miles to Empty" reading after corroborating the readings against the fuel gauge and getting consistent results when refilling the tank. When that number drops below 10, the tank will accept 19.5 to 20 gallons to fill up to the automatic shutoff. It's been that way for 2 1/2 years and 40K miles.

 

[Bayou_Tundra]

I consistently refill 23-25 gallons in my 26 gallon tank. I’ve seen some 25.5 gallon refills.

If I refill only 22 gallons I say to myself “ I could’ve kept driving.” When the DTE reads 0 I used to reset my trip B and could gauge how far I could go on the “reserve fuel”. I no longer do this. I know when it’s time.

But don’t be like me. Some would say I’m a bad influence on your fuel pump plus I don’t drive in traffic.

 

[OkSlim]

@Instrument53 You are putting too much thought in it.

I have driven either via company gas card or paid for mileage since forever.
Before we get started, are you getting a car allowance on top of the 21.3 cents?
If not you are getting screwed . Especially if you drive a lot of miles. If you aren't getting a car allowance you should be getting the max IRS for mileage.

Anyway, I just use my
A trip meter for mileage per tank
B for knowing when to change the oil.
C for total miles.

At my old job we just used to have to put the miles driven on our receipts.
Then we went to having to put the mileage on the odometer when we got gas on the company card and keep track of total miles for the month.

If you are worried about how the mileage difference between 60 and 70 is affecting your bottom line, you need to get a better job.

 

[OkSlim]

I consistently refill 23-25 gallons in my 26 gallon tank. I’ve seen some 25.5 gallon refills.

If I refill only 22 gallons I say to myself “ I could’ve kept driving.” When the DTE reads 0 I used to reset my trip B and could gauge how far I could go on the “reserve fuel”. I no longer do this. I know when it’s time.

But don’t be like me. Some would say I’m a bad influence on your fuel pump plus I don’t drive in traffic.

I have caught myself a couple of times driving 15 miles or so after the 0 miles showed left. But usually I try to not let it get under a 1/4 because the fuel in the tank is the lubricant for the fuel pump as well as the coolant.

 

[Instrument53]

Slim thanks for the input. Just checked the MPG and it came out to 18.5. Our company got bought out and we use to get 700 per month along with a gas card. That changed to 21 cents per miles and a reduced allowance to 492. So looks like there is going to e a mass exodus of the outside sales group. Poor guys in Texas all drive 3/4 ton 4wd diesels....

 

[crunch527]

Slim thanks for the input. Just checked the MPG and it came out to 18.5. Our company got bought out and we use to get 700 per month along with a gas card. That changed to 21 cents per miles and a reduced allowance to 492. So looks like there is going to e a mass exodus of the outside sales group. Poor guys in Texas all drive 3/4 ton 4wd diesels....

gotta love buy outs..."we can do it much cheaper..."

 

[H2O MAN]

The fuel light on my '07 begins to glow when there is about 8 gallons remaining in the tank, that tells me I have about 80 miles remaining at highway speeds. However, I prefer to never run bellow half a tank remaining.

 

[toymoco]

Any tips to improve distance to empty? Can we replace the tank wit a bigger one?

 

[Big Shasta]

Horsepower is work done over time. You are using more of it to push a 6000lb vehicle through a wall of air at 70 vs 60. Only way in your situation to get/use more HP is to burn more fuel. Can't hide from the physics.

You could put wooden panels all over the side of the truck to streamline it for better aerodynamics. LOL...Too lazy to find that guys pictures.

Don't run with the tailgate down, that hurts mileage.

I get .545 cents per mile when I drive for work. It's decent when I go on a key west trip. ~2K miles total for the trip. I burn about 300 in gas so I'm getting about 800 for "wear and tear".

 

[IamRay]

Any tips to improve distance to empty? Can we replace the tank wit a bigger one?

Transferflow makes a 46 gallon replacement tank. It's the one I'm considering. I'd like to go 10-14 days between fill-ups with my normal driving pattern.

 

[AG2]

Transferflow makes a 46 gallon replacement tank. It's the one I'm considering. I'd like to go 10-14 days between fill-ups with my normal driving pattern.

At fill up, the distance to empty considers your driving habits and MPG on your last tank of gas to estimate your anticipated distance on your new tank. But when you pull out of the gas station and hit a lot of stop and go traffic, your immediate MPG probably drops to 10 mpg. As you leave the gas station, the onboard computer recalculates your DTE based on your driving habits over the last few minutes on this new tank.
At least, that's the way I understand it and that's how I would design it too because your driving habits on that last tank of gas may be completely different than your driving habits today.

Sent from my SM-G920V using Tapatalk

 

[Bayou_Tundra]

26 gallons tank. Again don’t be like me. Be better than me. Refill soon as you see the light.

 

[AJFisaco]

Gas consumption is exponential in relation to velocity. For example, it takes almost 4x the amount of gas to go 80mph than it does to go 40mph.

 

[AG2]

Gas consumption is exponential in relation to velocity. For example, it takes almost 4x the amount of gas to go 80mph than it does to go 40mph.

Wind resistance is fuel-tile

:lol:

 

[Bushwacka]

I have an ‘11 5.7 that I purchased used in 2016. When I purchased it and filled up the first time Miles to empty read 302 (in winter in Northern Idaho). I’ve never been able to go over 304. That’s all year every day and every season. I mostly drive fwy speeds 75/80 and get average mpg ~13. Recently, I learned the tank capacity is 26.4 gallons. For a 26.4 gallon tank at 13 mpg that’s in the 340 range. Anyone know why it only goes to 302?

I’m the guy who drives till the gauge is at E and miles to empty was 0 ten miles ago (idiot light been on for days). When I fill up the auto shut off stops ~23 gallons. After checking the max capacity of the tank (26.4) I figured I can still put 2 - 2.5 more gallons into the tank. I have consistently got 2-2.5 more gallons In after the auto shut. Why does it shut off consistently 2 gallons shy of full?

I’ve noticed squeezing the additional 2 gallons of gas into the tank doesn’t change miles to empty. If I’m on E and fill up 23 or 25.5 gallons the miles to empty still reads 302. Why?

 

[Hicklebunny]

I have an ‘11 5.7 that I purchased used in 2016. When I purchased it and filled up the first time Miles to empty read 302 (in winter in Northern Idaho). I’ve never been able to go over 304. That’s all year every day and every season. I mostly drive fwy speeds 75/80 and get average mpg ~13. Recently, I learned the tank capacity is 26.4 gallons. For a 26.4 gallon tank at 13 mpg that’s in the 340 range. Anyone know why it only goes to 302?

I’m the guy who drives till the gauge is at E and miles to empty was 0 ten miles ago (idiot light been on for days). When I fill up the auto shut off stops ~23 gallons. After checking the max capacity of the tank (26.4) I figured I can still put 2 - 2.5 more gallons into the tank. I have consistently got 2-2.5 more gallons In after the auto shut. Why does it shut off consistently 2 gallons shy of full?

I’ve noticed squeezing the additional 2 gallons of gas into the tank doesn’t change miles to empty. If I’m on E and fill up 23 or 25.5 gallons the miles to empty still reads 302. Why?

Sounds like you need to put a full gas can in your truck, then drive it until it sputters. Then check how many miles you have gone.
Let us know how it works out.
P.S. I claim no responsibility for any damage done to your vehicle in the pursuit of our entertainment.

 

[Bushwacka]

Yeah. Let’s avoid that.