I have a '99 2500 with the fuel gauge stuck on full after I start the motor.
Any idea what's causing this.

 

Wish mine was full everytime I started the truck

 

mine does the same thing it started out that i would run out at about and 1/8 of a tank or so i was told by the steelership. then about 8 months later i found out the hard way that it would run out at about 3/4 of a tank. now it doesnt move at all ever. i think it in the sending unit in the tank. there was a thread on it somewhere

 

Is it still under warranty? Take it back in there and have them fix it.