Anyone using Distance to Empty?
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Joined: Dec 2013
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From: SE Michigan
All these answers and no one is answering his towing question. I believe that the towing mileage is determined by hooking up to the 7 pin instead of the 4 pin plug. I don't know if you have to have electric brakes or not, but clearly that's something you'd be able to find out when you first hook up, either it will show you towing the trailer or not. I can tell you that using the 4 pin connector it does not know it's towing.
As far as DTE, my understand is that some vehicles have a fuel pump that sits inside the fuel tank and is cooled by the fuel it sits in (my 2006 Dodge Caravan that my son ran dry twice). That pump was on risky ground I was told, so I replaced it before I sold it to not have any issues. Other vehicles have a fuel pump located outside the tank, and I thought I read on the forum that the pump is located outside the tank on the F-150. Regardless, running it dry, and cranking with no fuel in it, are all bad things.
I've never got to zero, and I've put as much as 32.5 gallons in. On my recent trip which included 4 hours in Canada (more expensive gas), I put in enough to get 100 miles into the US knowing I would get gas 50 miles in, and put in the 32.5 gallons.
2013Lariat4x4, you've got some good habits. I record what I put in and what the truck says on all the measures (mpg, gallons used, etc.) and find that the MPG is always 0.5 to 1 too high on the truck (and my Ford Fusion) and the gallons used is around 0.5 too high. I always check the calculation, knowing that if I have a 1/2 tank and I'm currently getting 14 mpg that I need to get gas before I go close to 252 more miles.
As far as DTE, my understand is that some vehicles have a fuel pump that sits inside the fuel tank and is cooled by the fuel it sits in (my 2006 Dodge Caravan that my son ran dry twice). That pump was on risky ground I was told, so I replaced it before I sold it to not have any issues. Other vehicles have a fuel pump located outside the tank, and I thought I read on the forum that the pump is located outside the tank on the F-150. Regardless, running it dry, and cranking with no fuel in it, are all bad things.
I've never got to zero, and I've put as much as 32.5 gallons in. On my recent trip which included 4 hours in Canada (more expensive gas), I put in enough to get 100 miles into the US knowing I would get gas 50 miles in, and put in the 32.5 gallons.
2013Lariat4x4, you've got some good habits. I record what I put in and what the truck says on all the measures (mpg, gallons used, etc.) and find that the MPG is always 0.5 to 1 too high on the truck (and my Ford Fusion) and the gallons used is around 0.5 too high. I always check the calculation, knowing that if I have a 1/2 tank and I'm currently getting 14 mpg that I need to get gas before I go close to 252 more miles.
Last edited by Ricktwuhk; Mar 3, 2014 at 09:16 AM.
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I have only owned and operated one vehicle with a trip computer. It had one only because I built it. I manufactured and sold trip comuters for BMW K model motorcycles from '91 to '08. The product name was Fuel Plus. I say was because the recession killed the after market business for me.
A trip computer cannot predict changes in consumption but it can calculate on the fly and give an accurate DTE while consumption varies. Occasionally I would discover my range was close to the distance to a town that should have fuel. A decision I made one Sunday afternoon at an isolated convenience store was to not buy fuel there because 1. no premium, 2. I didn't trust the fuel to be water free. I showed 35 miles remaining on the tank and the distance to the next town was 35 miles (posted). Don't trust all mileage signs! I chose to run to the next town because I knew I could make it. My trip computer has a tracker feature. Enter the destination (35) and it will give the difference of range and remaining distance (+ -) miles. Zero or positive is what you want. I had gotten to negative one and had to slow down to catch back up. Catch up must be done early enough to have enough distance to gain it back. I backed off to 55 for about 5 miles to get back to zero. The range showed one and the motor was still running at the pump.
That being said it's not my preference to run it close but when needed you have to know if the computer is telling the truth to rely on it. I intend to tow my boat to the lake and back each trip. Currently I can make it on one tank in my old truck. I have no idea if the F-150 will do it. It's one stop I don't have to make if it will. It's not a big deal if it won't but if it's close I want to know so I can make the decision where to stop.
I don't know how Ford programmed their computer but I suspect the range is not calculated from the economy figure. They publish that the average distance for DTE is 500 miles. That should be a running average. There is no reset for that as it is taking the last 500 miles consumption and multiplying the fuel remaining to get the range. Anyway that's how I do it EXCEPT not for 500 miles! It needs to be more like 40 miles to allow changes in consumption to filter into the calculation. That will give you an update much sooner.
In my testing on the motorcycle I ran the tank empty several times. As for overheating the pump motor, it cannot run out of fuel because when the pressure drops the engine falters and quits which powers off the pump. Never had a problem. I can't say what the Ford will do but I will find out and let you know.
My experience with fuel tank capacity has been that the manufacturer states the WHOLE volume of the tank. The usable volume is the whole volume minus the pump and other parts inside, minus the volume below the pickup tube. My Chevrolet Duramax had a stated volume of 36 gallons. Actual is 34. That can only be determined by running it empty then measuring the fill-up volume. I will do the same on the F-150.
If Ford is using the gauge float for measuring it can't be accurate. If they are using the injectors for measuring it can be accurate. If they are actually averaging over 500 miles the average is not useful. My computer was user selectable from 1 mile to .... can't remember the limit but much higher than is useful.
I have not emptied the first tank yet and it will be awhile if this weather keeps me off the road.
I have a couple of questions. The computer stores normal history and towing history. How does it tell there is a trailer? Do I need to select which history to use in the settings when I am towing? The manual does not explain. See page 124, DTE calculation.
Thanks for all your input.
A trip computer cannot predict changes in consumption but it can calculate on the fly and give an accurate DTE while consumption varies. Occasionally I would discover my range was close to the distance to a town that should have fuel. A decision I made one Sunday afternoon at an isolated convenience store was to not buy fuel there because 1. no premium, 2. I didn't trust the fuel to be water free. I showed 35 miles remaining on the tank and the distance to the next town was 35 miles (posted). Don't trust all mileage signs! I chose to run to the next town because I knew I could make it. My trip computer has a tracker feature. Enter the destination (35) and it will give the difference of range and remaining distance (+ -) miles. Zero or positive is what you want. I had gotten to negative one and had to slow down to catch back up. Catch up must be done early enough to have enough distance to gain it back. I backed off to 55 for about 5 miles to get back to zero. The range showed one and the motor was still running at the pump.
That being said it's not my preference to run it close but when needed you have to know if the computer is telling the truth to rely on it. I intend to tow my boat to the lake and back each trip. Currently I can make it on one tank in my old truck. I have no idea if the F-150 will do it. It's one stop I don't have to make if it will. It's not a big deal if it won't but if it's close I want to know so I can make the decision where to stop.
I don't know how Ford programmed their computer but I suspect the range is not calculated from the economy figure. They publish that the average distance for DTE is 500 miles. That should be a running average. There is no reset for that as it is taking the last 500 miles consumption and multiplying the fuel remaining to get the range. Anyway that's how I do it EXCEPT not for 500 miles! It needs to be more like 40 miles to allow changes in consumption to filter into the calculation. That will give you an update much sooner.
In my testing on the motorcycle I ran the tank empty several times. As for overheating the pump motor, it cannot run out of fuel because when the pressure drops the engine falters and quits which powers off the pump. Never had a problem. I can't say what the Ford will do but I will find out and let you know.
My experience with fuel tank capacity has been that the manufacturer states the WHOLE volume of the tank. The usable volume is the whole volume minus the pump and other parts inside, minus the volume below the pickup tube. My Chevrolet Duramax had a stated volume of 36 gallons. Actual is 34. That can only be determined by running it empty then measuring the fill-up volume. I will do the same on the F-150.
If Ford is using the gauge float for measuring it can't be accurate. If they are using the injectors for measuring it can be accurate. If they are actually averaging over 500 miles the average is not useful. My computer was user selectable from 1 mile to .... can't remember the limit but much higher than is useful.
I have not emptied the first tank yet and it will be awhile if this weather keeps me off the road.
I have a couple of questions. The computer stores normal history and towing history. How does it tell there is a trailer? Do I need to select which history to use in the settings when I am towing? The manual does not explain. See page 124, DTE calculation.
Thanks for all your input.
Running it dry is a very good way to kill a pump. I've seen it many times. Within 6 months of running it dry, the pump dies quite often. On a new truck you can probably get away with it, but I wouldn't.
I'm fairly certain that it uses tow/haul mode to determine which mode it is in. But it could also be through having a7 pin plug connected. And my dash cluster gives the option to use the towing history or regular history for calculating DTE. That tells me you have to select it every time you switch.
Also, there are people who have put about 30 gallons in the 26 gallon tank when pumping very slow.
The gas needle uses a float. That is certain since parking on a hill will change it. The screen that shows fuel used will be based on injector pulses. I'm betting the DTE will be based off of the tank float since that is the only way the vehicle has of knowing the volume in the tank. But am unsure. In fact parking on a hill will change the DTE, so definitely based on float. I would not trust it.
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From: Timbuk3, MI
Ford850 - I use it how (I think) it was intended. When on a highway or interstate with exits spaced many miles apart, or when traveling in remote/rural areas, I watch the DTE. It gives me a quick and rough estimate so I can decide when to refuel and when to wait for the next exit or town.
Any other use of the DTE # is a SWAG (Scientific Wild *** Guess).
.
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Joined: Dec 2011
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Accurate distance to empty does not seem to be one of Ford's strong points. Maybe it is due to shape of tanks. On my 05 Powerstroke it said I could go 14 miles and I ran out after six on level ground while driving as conservative as possible.
My current 2011 will read say 30 to go and start dropping rapidly in the mile numbers long before reaching anywhere close to thirty, again on level ground driving conservatively to save fuel. I know this and fill up accordingly, but I am sure there are folks that run out by trusting the distance to empty readout.
On the BMW cars I have had if they calculated I could go thirty miles, I could go thirty miles. Very reliable.
My current 2011 will read say 30 to go and start dropping rapidly in the mile numbers long before reaching anywhere close to thirty, again on level ground driving conservatively to save fuel. I know this and fill up accordingly, but I am sure there are folks that run out by trusting the distance to empty readout.
On the BMW cars I have had if they calculated I could go thirty miles, I could go thirty miles. Very reliable.
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Joined: Apr 2013
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It sounds like I'm in the minority but my last two trucks had DTE meters and I routinely let it get into the single digits without any issues. I' ve seen 0 on the meter more times than I care to admit but never ran out of fuel
I rarely fill the tank to the top, generally just put in $40-$50 when it gets low since there is a gas station every other block where I live. I don't have the patience to stand at the pump long enough to fill it to the top and besides, why haul all that extra weight around?
Regarding low fuel levels and fuel pump failure. I have driven several older, high mileage vehicles (150,000 plus) in the same manner, often bouncing the needle off empty before adding a few gallons. I only recall ever replacing one fuel pump.
It's probably not good for it but maybe I saved a few dollars is suspension repairs over the years by not hauling all the extra gas around
I rarely fill the tank to the top, generally just put in $40-$50 when it gets low since there is a gas station every other block where I live. I don't have the patience to stand at the pump long enough to fill it to the top and besides, why haul all that extra weight around?
Regarding low fuel levels and fuel pump failure. I have driven several older, high mileage vehicles (150,000 plus) in the same manner, often bouncing the needle off empty before adding a few gallons. I only recall ever replacing one fuel pump.
It's probably not good for it but maybe I saved a few dollars is suspension repairs over the years by not hauling all the extra gas around
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Joined: Nov 2010
Posts: 11,854
Likes: 2,559
From: Timbuk3, MI
Pacific Fisher ... On the BMW cars I have had if they calculated I could go thirty miles, I could go thirty miles. Very reliable.
I didn't think so.
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Last edited by gDMJoe; Mar 3, 2014 at 10:04 PM.
Thread Starter
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How do I get Ford to answer my questions on the DTE function related to towing or not towing?
How does it know I'm towing? I have surge brakes, not electric.
Are these service department questions?
Does Ford have owner support?
Thanks guys for all your input. Still on my first tank.
How does it know I'm towing? I have surge brakes, not electric.
Are these service department questions?
Does Ford have owner support?
Thanks guys for all your input. Still on my first tank.
