overhead Computer & fuel mileage...

[CRegal]

Hey folks, I have been noticing that my DTE (distance til empty) gauge on the overhead computer seems to be off. When it reaches 0 miles left, My fuel needle reads in the Red on E, but when i stop and fuel up, I can only put 30 gallons in. That leaves 5 gallons that are apparently still in the tank.



I am getting about ~470 or so miles out of a tank, & on my 5 speed 3500 with 4. 10's i got around 530 or so. My question is:

Why the difference? I do know my 01 is styll new, but is there really a discrepancy with the fuel readings? Do I really styll have 5 gallons of usable fuel? It reads me about 15 mpg and if that is true I should have 75 more miles to go once I hit 0 on my dte gauge.



Some of the things I have done is always fill up to i see the fuel in the neck of the filler, so as to have a good judge of how much is really in the tank to start. I also fill up at the same fuel stop.



Also I have been running empty the whole tyme, on similar trips. My 99 gave me a good 100 miles before I came down out of the F mark on the gauge. Now I am lucky to get 50.



Any advice or feedback would be greatly appreciated.



Cole

 

[B.G. Smith]

It seems that all the trucks have about 7 gallons of fuel left when the low fuel light/bell comes on. The computer uses the fuel level indicator(gauge) to determine fuel left in tank and multiplies whatever it reads(empty, 1/4 tank, etc)times the fuel mileage that the computer is currently showing at the time to determine the miles till empty or dte miles. bg

 

[Idaho Native]

CRegal,



Noticed the same thing on my '99 when I bought it... accurate to within about . 3 mpg when stock. Distance to empty was about the same as yours. Could put a max of 29 gallons in the 34 gallon tank (QC Short box) when on 0 DTE.



After bombing, it goes out the window I think KatDiesel put a thread on the site somewhere about why it goes T. U. after a performance box is added... basically the computer gets an erroneous reading about fuel used based on throttle position. I haven't really checked my DTE since BOMBing... got to assume (I know that's dangerous) that it's also probably in error now.



Cheers,



Loren

 

[Mundgyver]

From experience with mine, when the light comes on, if I fill at that point and top out the tank, I find that I have exactly 9 gallons of fuel in the tank. Longest trip I have done is 715 miles at 22. 3 mpg with 3. 4 gallons left in the tank. I'm heading out tommorow night on the same trip with the new big scremin filter installed (big honkin filter on the other post) and look forward to seeing if I can improve this. I will run the same pace I did last time. 65 mph. Most fuel I have put in is 33. 6 gallons.