fuel gauge problem

[motorhead]

On my 2005 LLY 3500 CC, LT,4x4 all stock with hide-away gooseneck hitch.

I am having an issue with my fuel gauge not indicating accurately.
Indicates full when tank is full.
Indicates low fuel and light at 25 gal used on DIF. Refilling at this point takes +/- 25 gal.
Have usedd down to DIF reading 32 gal used and refill at this point takes +/- 32 gal.

This is a re-occuring reading and repeats consistantly, no floating or bouncing of pointer. DIC is repeating it's reading accurately as well.

I have been having this problem since purchase. Contacted previous owner who says never had any problem. Have been to local dealer to check TSB for electrical issue with insturment cluster and they say no indication of electrical problem. I have inquired if there is any parameter in the program that would change the reading of the gauge and they say no, need to replace the sending unit.

Does anybody have information that would help?

 

[btfarm]

First of all Welcome to The Truck Stop! :welcome8:
I take it you have a long bed with a 37 gal tank.
My guess off the top of my head is your BCM isn't programmed for the right tank or maybe your local dealer is correct and the sending unit is fubar.

 

[WarWagon]

Dig harder for a TSB. I know 2008's have one for the fuel guage accuracy. Try some fuel system cleaner. Otherwise fuel tank senders go out often.

 

[tractor]

Find the wire going to the sender that is the ground wire and ground it to the frame and see if that fixes your problem.Have done that to a few with same problem and has solved it.
Darryl