Canaminator

I have got a 2005 3500 ( not dually ) SLT. The fuel guage has never worked properly so last weekend I had the fuel pump/sender combo replaced in the tank and the fuel guage is still reading whatever it wants. I currently have about 1/4 tank and it reads full. After the first install of the new unit the guage appeared to be working ( moving progressivley down as the truck burned diesel.) and then suddenly it will drop to empty and sometimes slowly climb up to read approx what I assume should be the correct level. Then creep up to full and now today I am almost empty ( counting mileage ) and it is reading full to the nuts. This thing is driving me nuts. I crawled under the truck and checked and wiggled every wire and connector from the tank to the fenderwell but no luck. I need help.

gcssr

http://www.dodge.com/bodybuilder/200...tionsystem.pdf
Try this link, from what you are posting, your problem is a bad ground, In the middle, you will see an in tank, pump and sender diagram, follow the wire (DB/DG) I believe that to be your ground. (Diagram 8w30-3) Hope it helps Grant