My 2001 long box CTD is supposed to have a 35 gallon fuel tank, right? Well, when the needle is on the lowest line on the gauge and I fill her up, I only put in like 24 gallons. So I should have had 11 gallons left in the tank. I'm sure the gauge isn't that conservative, so does anybody have an idea what the problem is? Even my overhead display thing says I'm down to about 50 miles for the distance to empty and yet I can only put in about 24 gallons. any thoughts?

 

Sending unit could be going bad. However, mine would still read 1/4 tank when I ran out. Never really heard of them failing the other way.

 

Mine is the same way , i have a 130L tank (i have no idea what that is in gallons , but work with me here) And when the gauge gets down far enough that the lowe fuel light comes on , i can only get about 100L into the tank , so my gauge is lieing to me.

 

That seems to be a pretty common experience.

I wonder if Cummins/Dodge built them that way to ensure we'd never run out of fuel. (Diesel injection systems can be a HUGE pain to bleed air out of).

Another thing to remember is, the Cummins uses excess fuel pumped forward from the tank to cool the injection pump, then it's returned to the tank.
The less the amount of fuel in the tank, the hotter the fuel pumped forward.

 

My '02 is the same way. It never takes near the amount listed in the owners manuel for tank capacity, even with the fuel light on, and I top off.

 

How far do you fella's drive before the gauge starts to move off of F? I go anywhere from 30-50 miles , sometimes a little more , before it starts to move.

My dad's truck goes 150-200KMS before it comes off of the F mark , but he also gets 1000+ KMS to a tank (650-700+ miles)

 

Mine reads empty early too. I just use the ODO now. 500mi = fill up time.

 

Mine went 377 miles! Of course it's broke!

 

Yep mine goes right at 500 miles for fill up, and my guage will dead sit on Full for prolly 75 miles before starting to move.