The 2013 F150 owner's manual page 124 says the DTE history can be selected from normal or towing conditions.
Does anyone know for a fact when to select either?
Does the computer know when the truck is towing and store consumption in the appropriate history?
I have surge brakes so it cannot detect electric brakes to switch from normal to towing.
Do I have to select the desired history manually for towing or not towing?
Ford needs to explain what to do and how it works. I find nothing.

I want to use DTE but I need to know it is working correctly.

Anyone "know" (not a guess) about this? I have received 48 posts on another F150 forum and no one there actually "knows".

Ford, where are you?

 

Yeah if you are towing the truck will recognize the trailer brakes on the trailer. Also you're towing mpg will be around 10 mpg vs empty mpg of 18-20 so therefore you're DTE will be different if you have towed 1/4 of that tank. When I am towing I also go off of the Gallons used vs the DTE while towing.

 

What model truck do you have? If you have the upscale information display in the gauge cluster, than it is easy to do. You have:
Gauge mode
Trip A/B
Fuel Economy
Truck Apps.
Settings
Information.

Hit the down arrow to "Settings",
now hit the right arrow to enter into the settings list.
Then go down till you come to DTE calculation.
Hit the right arrow to enter either "Normal History used", or "Towing History used". Then hit the center OK button for your choice.

It's about that simple. Now if you have the regular basic information display I don't know if that is available on it.

I change mine every time I tow my Polaris Ranger. Hope you get it figured out...

 

I don't think it will with surge brakes.

 

I have the information display and it is set to normal. So far this is the best info I have received on this matter. Please answer more.

Can someone confirm the DTE calculation will switch automatically when electric brakes are connected and back to normal when disconnected?

 

No. You have to do it manually each time you hook up your trailer, and switch it back when you unhook it. Also, Under Truck Apps., you can add a trailer, name your trailers, Change active trailer, reset traveled mileage for each, or delete a trailer. It will also show accumulated mileage for the default trailer, or each trailer you have named
Go to
"Truck Apps."- Trailer. Then go to "Options" to make any changes.

Also under "Settings" (which is below the Truck Apps. heading), you can set up your trailer brake mode for either electric brakes, or electric over hydraulic.

Go to
"Settings" - Driver assist - Trailer brake mode. Change it there.

It's a bit confusing at first but gets easier. Believe me, I know. I am not a computer guy in any way. I have two set ups for the same trailer. The first one I call "Ranger", for when I'm towing my Polaris Ranger in the trailer. The second one I call "Empty", for when it's not loaded. The Ranger and it's gear is around 1,500-1,600 lbs. or so so it does make a bit of a difference. So any way, I hope that helps you out a bit...

 

If the trailer has electric brakes as soon as you plug in the trailer's connector the trailer should be recognized. Even if you have a small trailer without brakes (I have a small 7x12 for my Polaris RZR XP900) I go to the trailer screen and make "RZR trailer" my active trailer. This does two things. One it keeps a running total of how many miles I have on the trailer. This tells me when to grease the wheel bearings, etc. Second the computer keeps track of my (sorry) towing fuel economy in the trailer DTE calculation.

As was stated you have to manually select which one that you want to use. Having said that sometimes I will have been towing and switch over to towing DTE and see what it says, then switch back to normal, then switch back to towing DTE. Sometimes the normal shows that I have fewer miles to empty than the towing DTE. So I don't put much faith in it. Like one poster above said, I go by gallons used on the Trip odo. If I am getting 9mpg then when it gets near 30 gals used I start looking for fuel

 

Now I'm getting more confused. Are you saying the "towing" DTE also differentiates between the trailers in your list?

This may all be a moot point if the calculations show more miles left with towing than without. Something must be wrong.

 

When you hook up your trailer, I'm not sure if it registers as the Default trailer, or goes back to the last one that was selected by you. In any event, the DTE is calculated with whatever trailer is displayed. And if your gas mileage differs for each trailer then the DTE should differ as well. Now I haven't tried this myself because I haven't thought about it before. But it makes sense. It would also then make sense that if you zero out a trailers mileage traveled, then there is no memory for DTE, and it should then recalculate mpg as you travel. Also, I think switching back and forth between normal and towing DTE isn't a good indicator because there are too many variables. I know that as I travel out to West Virginia that my DTE changes even as I go up inclines, and then back down. On one trip I looked at it and it said 333 miles to empty. But then a bit later it went up and said 426, not down. The difference was that I switched directions and was then going with the wind, an mostly down hill and on level ground for a time. So less throttle meant better mpg which then upped the DTE calculation. So it constantly changes with road conditions and how you drive.

 

I just emptied my first tank. It took 36.87g to fill it. I noted the usable capacity in the truck log.

I know others are concerned about running the pump dry. I looked at the tank and I see a sump at the rear. I suppose the pickup is there. If so that would leave fuel in the sump when stopping or going down hill keeping fuel supplied under a low fuel condition. I felt the bottom and sides of the tank for a temperature difference and detected none. I don't think the power to the pump raises the fuel temperature therefore does not overheat the pump. Actually as soon as air gets to the pump it quits creating pressure. That should be the cause for the engine to stop. I ran 66 miles past zero miles to empty. I let the engine idle until it died. I started it and it ran a few turns and died again so I know it will not run once it gets air.

I discovered TRIP. Trip A says I used 38.8 g and that is exactly what I pumped into the empty tank. That tells me the computer is accurately measuring the fuel.

Question, if I zero the trip A at fill up it should tell me how much fuel I have used, right? I then know what is in the tank at any time and can compute range. However the computer needs to do that. Do I need to zero the economy when I start the trip and will the DTE compute it on its own.

I'm not understanding the how it all ties together. Looks like the engineers have again put too many functions in and has given us absolutely no instructions on how to use it. I don't see the need for trailer selection. It doesn't matter if there is a trailer or not. Range is calculated by consumption and fuel remaining. The load change of a trailer or no trailer will cause consumption to change, the computation is the same. If you reset the economy will DTE calculate from the new economy? If so just reset it when you start a trip, period.

Scarlet, your experience with the DTE changing with load gives me hope that Fords computer is useable. It does need to adjust for changes but at a rate that makes sense. The DTE description says it averages over 500 miles. That is absolutely useless! It needs to be around 40 miles give or take. The range changes you experienced had to be for a much shorter distance than 500 miles. What do you think allowed it to make quicker calculations? <<<<< this is an important clue to understanding how it works.

FYI, I designed and sold a trip computer for BMW motorcycles from 1991 to 2008. I was called Fuel Plus. The recession killed my business, 90% of my sales were on the West coast. My computer took a running average that was rider settable. That allowed changes in load to factor in as they changed. I've rolled up to the pump more than once with 1-5 miles left knowing I could make it. The only way to stretch your range is to slow down and you can't expect much of an increase unless you have been running 80 or more.

So much for that, I want the Ford computer to tell me where I can fuel with confidence. It will allow you to make an instant decision to stop now or go farther and NEVER run to empty. Done it for years on the bike. Using more of the tank means fewer stops and more time at your destination.

Looking forward to your replies. I think the computer can be used accurately and in simpler fashion than described so far.

 

As Scarlet said DTE is for all trailers averaged together.

Yes, just reset either Trip A or B and use that to keep track of gallons used and you should be fine.

The "instant fuel economy" indicator has no relation to the DTE and as far as I know neither does Trip A or Trip B odometers. The computer is always keeping a constant count of gallons used vs gallons in the tank and giving you an estimated DTE.

If you just buy one gallon of fuel and dump it in the tank the DTE will go up and this is without you resetting or touching anything.

 

What I do is I Zero out both A and B at fill up. I use trip "A" as a "Per tank full" monitor. I use "B" as a "Per Trip" monitor. Then at the next fill up I right down the trip "A" figures and also calculate the figures by hand at the pump. The trips monitor is usually pretty close. Unless I warm up the truck in winter or cool it down in summer it's usually within a half gallon. At home I have a spread sheet that I keep a running record of the trucks gas mileage. I think it's better to use the trip monitor as a gauge of fuel used. Like I said when I calculate my tank full mileage it's pretty much on. The DTE changes constantly as you travel due to road conditions, weather and how you drive. The computer monitors how much fuel has been added, then calculates the mpg against the miles since the last fill up. Now I'm starting to confuse myself, lol.. I'll find the screen shots if I can, but like I said on more than one trip out to West Virginia the DTE changed drastically up and down because I was traveling thru some mountains. At one point it said about 333 miles, then a bit later it said like 426 miles. It went up. I've only used the towing calculation on the past two towing trips and I don't have any records of those yet. But they're coming. I'll be towing a bit more this year.

 

I didn't mention that after running dry and trying a start that failed I added two gallons to the tank. When I started the engine it started as usual without hesitation. That tells me that should I ever run out (never have accidentally) it will not have a restart issue.

After adding the two gallons the range went to 43 so like you said it is measuring what is added. The only time I do a partial fill is when the pump shuts off at a $ limit and I'm in a hurry to get rolling in town, not highway.

I am on my second tank, still not towing but will monitor the trip data and compare it to the DTE to see if it will follow it. I prefer the DTE to follow the changes in the load as it will give a closer actual range should I need to push it close to empty. Again I prefer it to average over about 40 miles, not 500!

When the DTE was changing in the mountains it could not have been averaging over 500 miles as stated in the manual. There would be no change except for the reduction of fuel in the tank. Scarlet, were you using instant economy? ////// Something was causing DTE to average over a much shorter distance. I would like to know what. ///// Scarlet, try to recall how you were using it then, please.

As for DTE averaging all the trailers, what's the use if that. I still think parsing the consumption based on the trailers makes no sense. Consumption applied to fuel remaining is all that needs to be calculated. Works the same for any load. On the motorcycles if a bike has a side car or trailer it simply gets less range. Nothing is changed in the computer for one rider vs. two or how much weight is carried or pulled.

I'm going to approach using the computer without any trailer settings. I have surge brakes so it won't detect my trailer anyway. Again it simply will have an added load and more fuel consumption. It should still compute. I won't be able to test the trailer until boating season in May.

 

It sounds to me like you are going to all this trouble so you can run the tank down to fumes before you get gas. This is not a good idea, your fuel pump life may be shortened because the fuel pump is cooled by being immersed in fuel. You also run a risk of sucking up crap in the bottom of the tank, and your truck does not have an easily replaceable fuel filter, it's IN THE TANK and attached to the fuel pump.

 

When I was telling you about the DTE fluctuation it was as I said. If you PM me your email address I can send you an attachment of photos from a trip I took last year in June. I have a series of photos I took of the display as I was traveling out to west Virginia. The time frame of the series of photos is about three hours, and I traveled about 187 miles during that time. The DTE started 429 miles to "E". At the end of those three hours and 187 miles, the DTE then read at 449 miles. Yes, the DTE said I gained 20 more miles to empty, while I had traveled 187. Now that is funky..... Hey, pictures don't lie. It fluctuated between 402 and 444 until the shot at 449. At that point I stopped taking pics.. It's because of the variables. That day I was going mostly with the wind behind me. Also, The tank or two prior to that was mostly local driving so the MPGs for that time frame would of been considerably less than what I was presently getting on that trip. Around town at the time I was probably around 12-14 mpg, while on this trip I was at about 20 mpg or so. You'll see in the photos. So I'm guessing the computer had calculated the DTE at 12-14 mpg at fill up. And then was re-calculating as I was driving with the better mpg. At least that's my guess?...