[dieselguy147]

well i got my gauge to start working again after the airdog install. now today while driving it said about a half of tank and i know thats how much i had in it. then the next time i look down it says past full and is staying there all the time now. what could it be this time? im supposed to leave on a roadtrip tommorow and sort of need a fuel gauge

 

[clc]

I don't know about the newer ones but I have read about gauge problems on the older trucks an I never have trusted the gauge on my 98.5. It sits on full for over 100 miles and only holds 25 gallons when the low fuel warning light comes on. I don't like to run mine low so I don't mind filling up every 500 miles. I Keep an eye on miles driven since the last fill up in case the gauge starts lying in the other direction.

 

[Whippit96]

How does you truck have a 25 gallon tank CLC? All the 2500 and 3500 cummins trucks have a 34 or 35 gallon tank.

 

[CUMMINS114]

sounds like you messed something up when you put the air dog in at the sender. assuming you pulled the stock one there is a little pivot screw slot where the sender rides up and down, it may have stuck causing it to malfuction or "hang up". sounds like your goin to have to drop the tank or remove the bed again.

 

[clc]

How does you truck have a 25 gallon tank CLC? All the 2500 and 3500 cummins trucks have a 34 or 35 gallon tank.

It IS a 34 gallon tank but the low fuel light comes on with 9 gallons in the tank which is OK because I would get fuel at 14 tank anyway. If only the gauge were linear and correct. It can't be full at 100 miles since a fillup and 1/8 tank equal 4.5 gallons, not 9. I have never dropped the tank on the 98.5. It might be that I could bend the float arm and make it close.