[05cumminsktm]

So I've noticed since I bought my truck back in September, that even after I 'fill up' the gauge would never go much over 3/4. I can run the truck down to where the lie o meter says I only have 20 miles left, 'fill it up' with 20-22 gallons, then drive home, let it sit a while, and then dump some in out of a can but it's hard to get a gallon to fit. So I'm assuming 'E' isn't really empty? Definitely don't want to test that theory by running it past 'E' though. So here's my question, I'm about to install an airdog, is there anything I can check-fix-replace while I'crazo got the bed off to try to fix it?? Thanks?

 

[BlueBalls]

So I've noticed since I bought my truck back in September, that even after I 'fill up' the gauge would never go much over 3/4. I can run the truck down to where the lie o meter says I only have 20 miles left, 'fill it up' with 20-22 gallons, then drive home, let it sit a while, and then dump some in out of a can but it's hard to get a gallon to fit. So I'm assuming 'E' isn't really empty? Definitely don't want to test that theory by running it past 'E' though. So here's my question, I'm about to install an airdog, is there anything I can check-fix-replace while I'crazo got the bed off to try to fix it?? Thanks?

With a long bed pickup you should have a 36 gallon tank.

My 03 QCLB 4x4 has a 36 (maybe 38) gallon tank.

Was your tank replaced after an accident with a smaller capacity maybe? Perhaps from a shortbed?

(Just realized that wouldnt affect your gauge reading. Do you have a family of soccer balls living in your tank?!

When I was a dumb kid and drove an F-150 my gauge was exactly like you describe. But the capacity was correct. You might have a dent in your tank that limits you from filling more than 22 gallons. Maybe your sending unit got knocked around and is out of calibration?

I would run it until your gauge reads empty, then crawl under the truck and knock around on the (plastic) tank. Should give you a general idea of how much fuel is in there... ?

 

[lonestarwelder]

Airdog with the Vulcan Liberty canister will solve all of that.

 

[05cumminsktm]

What exactly is a Vulcan liberty canister?? I've checked for dents, never found any. But never thought to knock on it when it says empty. Thanks for the ideas..

 

[klode]

your float on the sending unit might be sticking at 3/4..pull it out and clean where the float slides up and down...

i have a 36 gallon tank...FYI i drove on the hwy for an hour (60 miles or so) after the empty light came on...only because i had too. So yes, E isnt really empty

 

[05cumminsktm]

If it was just my sending unit wouldn't it take more fuel and just not move the gauge or would that shut the pump off too? That is, if it was just sticking at 3/4... Or maybe just always reads 1/4 lower than actual level. Out of calibration like mentioned. It says I'm 3/4, tank seems full. So maybe when it says E I still have a quarter tank?? I guess I'll have to knock around on it to see if I can prove or disprove that idea..

 

[600crpower]

When you install the airdog inspect the float on the fuel module. Make sure it can go all the way up.

 

[CumminsDieselSoot]

your float on the sending unit might be sticking at 3/4..pull it out and clean where the float slides up and down...

i have a 36 gallon tank...FYI i drove on the hwy for an hour (60 miles or so) after the empty light came on...only because i had too. So yes, E isnt really empty

According to dodge when the lie-o-meter says 0 on range left you still have 8% of you tank left, thats about when the dash light comes on. I driven till my guage bottomed out and didnt run out, but I was sweating it thou.

 

[klode]

If it was just my sending unit wouldn't it take more fuel and just not move the gauge or would that shut the pump off too? That is, if it was just sticking at 3/4... Or maybe just always reads 1/4 lower than actual level. Out of calibration like mentioned. It says I'm 3/4, tank seems full. So maybe when it says E I still have a quarter tank?? I guess I'll have to knock around on it to see if I can prove or disprove that idea..

It's is a resistor that the float is sliding on...It changes the signal from 1 to 5vdc wich represents 0 to 100% full. There is no "calibration" to be done...its either your slides are dirty or something fell out of place. Either way, you will have to pull it out for inspection and play with the float to see if the gauge will move accordingly. No use guessing whats going on cause the list of probobilities is high...There should be three wires going to the float (gnd, 5vdc and signal wire); if you jump the full 5V to the signal wire your guage should read full...if it dosnt, then its your gauge. It could even be a bad ground...they cause some weird happenings also!