Essentially you are running the truck for an extended period of time, and the truck shows that you have no decrease in fuel. This tricks trucks computer that the gauge is malfunctioning, and it defaults to empty. When you shut the truck down for a few minutes, it resets the gauge and will work properly until the computer notices it again.

 

I think you can fix it with EFILive too.

 

dumb question but what is EFI live?

 

Two ways that I deal with this is to manually shut off the tank
and run off the main tank. Then at night turn the valve on and refill the main tank. Now because I tow almost everywhere and on some days go through 2 or 3 tanks of fuel is to run the 50 gal aux tank empty, then put
50 gal in it and fill the truck tank. Reset the fuel used on DIC and watch that. When it says I have used 50 gal it starts on the main tank. I usually stop somewhere at that point and start over again. If you reprogram the computer to say you have a 75 gal tank it will cause your gauge to read funny for the last 25 gal or so.

 

who wants to watch mileage and estimate how much gas is in the tank. there must be a way to correct this computer glitch. i am glad you posted this because i was thinking about installing an aux. tank for long road trips hauling a 5er

 

Here is the way i look at it. I have a 60 Gal gravity feed in the bed. I fill both tanks when I'm pulling my 5er. Eventually the OEM fuel gauge will go to "E". One minute it's full and the next it's @ "E", so you know it's not really empty. As a double check, you can look at you DIC under the range and if you are really almost out of fuel, it will say either some low mileage or "low". In the above scenario it will just read "---".

Anyway, I drive forever on "E" and eventually you'll notice that your fuel gauge will again register "F". This is how you know when the aux tank is empty. So I use it like a fuel gauge in reverse for the aux tank. When my OEM gauge says "E" my aux tank is feeding it. When it finally reads "F" again, my aux tank is empty and I have a full tank of fuel to start looking at where next to purchase fuel.

Hope that makes sense.

 

:exactly:

Here is the way i look at it. I have a 60 Gal gravity feed in the bed. I fill both tanks when I'm pulling my 5er. Eventually the OEM fuel gauge will go to "E". One minute it's full and the next it's @ "E", so you know it's not really empty. As a double check, you can look at you DIC under the range and if you are really almost out of fuel, it will say either some low mileage or "low". In the above scenario it will just read "---".

Anyway, I drive forever on "E" and eventually you'll notice that your fuel gauge will again register "F". This is how you know when the aux tank is empty. So I use it like a fuel gauge in reverse for the aux tank. When my OEM gauge says "E" my aux tank is feeding it. When it finally reads "F" again, my aux tank is empty and I have a full tank of fuel to start looking at where next to purchase fuel.

Hope that makes sense.

Could not have said it better

 

Get an electronic fuel valve. Get one that is normally open. When the truck is on, power is sent to the valve and has it closed. When the truck is turned off, power dies, and the valve is open, filling your stock tank. In the time it takes to run out of fuel in the stock tank, you must have stopped for food or to piss, so when you stop, it fills up.

 

Best way to go "electric valve" you can use the same style used on late model fords with dual tanks just plug one end. I have this set up works great just takes about an hour to fill empty stock tank. Also if you want you can buy a electric fuel pump from any auto parts store and have a faster transfer but remember you risk over filling and diesel running out through overfill line.

 

i have the same prob with the fuel gauge....i have a 100 gal aux tank. i fill both tanks (134gal)...i reset the fuel used on the dic and just refill at around 120 gal or so.

 

Can someone recommend a automatic valve system to use with the aux. tank. The tank I purchased came without the valve or hook-up kit. Thanks in advance.

 

have any of you guys had a prob. with the fuel transfer tank not transfering all the fuel? i have 100gal aux tank and it does great but when theres about 40 gal left it stops transfering...then i run off the truck tank.

 

Sorry to be stupid but Im new to this transfering thing. I put 2 55gal drums in the back and put in a fuel pump to pump iinto the tank. All I had to do was plug a wire into the cig outlet and up the gauge would go. How does this gravity feed work? How does it know when to flow and when to stop? How come the tank doesnt overflow? Where do you all feed the hose into the tank? I have a fass pump and just T'ed it into the overflow line of the fass, bad idea? Last week I aquired a 110gal bed tank so I would like to set it up right. Last ? someone said that transfering was not exactly legal, not that I care just wondering if I need to hide all these hoses & stuff. Hell if I get dipped Im screwed anyway, I havent pd my road tax for all this bio

 

any reccomendations for a aux. in bed fuel tank? Would like about 40 extra gal.
thanks

 

Northern tool carries the RDS aux tank brand and transferflow.com a very nice one as well.

 

After having read the problems with gravity flow, I purchased a 6 port fuel valve/switch and now have a 2 position switch on the dash. The valve has electrical connections which allow you to also splice into the sensor wire from the OEM tank to the OEM fuel guage. The OEM guage works now for each tank and when the low fuel light comes on for one tank, I switch to the other. After a few tankfuls and refuelings of the auxiliary tank I know how many gallons are left when the guage shows "Empty".

 

Thanks

 

I would also like to have extra fuel on board. Can anyone explain to me where the aux. fuel line ties into the system? Do you tee into the fill hose? or the vent line?
Also, are there any issues with losing pressure in the main tank when the aux. goes empty? That is if I'm using gravity feed. If I use a valve on the line I don't feel this would be a problem. Any input would be welcome.

 

Mine ties into the vent line. The RDS gravity kits cut the fill line. The main tank isn't pressurized so no issues there. I didn't like the idea of my fuel guage not working with the gravity feed besides legal troubles when traveling to some states.

 

What stops the gravity feed from over filling the main tank and running on ground?
Thinking of welding my own stainless steel one, so any particulars will be appreicated.

 

I have the RDS Fuel/Tool box combo and it tied into the fillerneck of my truck. When I bought the box I bought the installation kit for about $35 and it has a hose barb with a check valve in it so when the fuel gets up to the filler neck it will raise a float and stop the transfer of fuel into the main fuel tank. I have not had it overflow my tank "YET" I tend to keep my manual shut off valve closed and run on my main tank until I need fuel then I open the valve which fills my tank in approx. 30 minutes. I usually open it when we stop for restroom breaks on long trips and try not to leave it open all of the time. Sooner or later I will buy an electronic valve but for now this works for me.

 

id like to know how to keep my gauge from going to f to E to F to E to F all the time too. Someone said efi live is this true?

 

That easy. run off you OEM tank. When it gets low turn on the gravity tank. when its full shut it off and just use the oem gage. The easy way to turn on and off the gravity tank is to install a pump or electric valve and switch it on or off from the cab. Mine has a light on the switch to help me remember its on. Its not perfect but its cheep.

 

Thanks, maybe my best bet is to buy the $35 kit and weld my own tank.

 

I have gravity feed on mine also. Made the mistake of leaving it on more than once. It does just what you said. The only thing I would be concerned about leaving it on is shorting out or messing up the fuel tank sending unit. Since these are rather exspencsive. I run my OEM tank til about 1/4 left. I was hauling RV"s , I would open the valve, climb back in and hit the road. It would take 2-4 hours, depending on load (mpg) and I would pull over and turn the valve off. What is it, 5 feet? takes about 10 seconds. From time of Park to enter Drive again. I loved driving across 1/2 the country and not having to fill up. I am a big fan of filling up at truck stops, fresher fuel, less problems.

 

Gravity feed is only illegal if it dumps directly into the carb or fuel injection system; at least that is what I have read. The going to "E" problem will only happen after driving about 50 miles or so. I do a lot of stop and go type of activity during the week, so it is never an issue unless I go longer distances. I'm going to try to turn the fuel valve down so that it only trickles out, and see if that works, but it really doesn't bother me at all. I love the extra fuel storage. I use the gallons used function of the DIC to keep up with what I have left in the tank. I have had the tank for about 10 months now.

 

ok thanks

 

fuel valve

what kind and where to buy the electric fuel valve, I know you have to get one that works with gravity flow

 

what kind and where to buy the electric fuel valve, I know you have to get one that works with gravity flow

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