Gas tank switch/tank selector valve/etc.

[jt]

Need help...Do you have any suggestions on what I need to do....have a 1985 silverado with a 305....the truck has a gas tank on each side...the switch that you
pressed to choose tanks quit working...replaced switch...still not working...at dealership suggested replace tank selector valve...replaced...now both tanks register full (this was not the case before beginning repairs) even though L tank is approx.  between 1/4 and 1/2 and R tank is probably less than 1/4.  Really
don't know except I know neither is full.  Do you have any suggestions as to what should be done in order know how much gas is in each tank...If you know a fix it would be greatly appreciated. Thanks J.T.

[NEMESIS]

mine does the same thing on my 81, but if i keep on pushing the switch a few times then it'll start to read correctly after a few seconds. i dont know if youve tried that already but its worth a shot.

[rolson1039]

i had this same problem with an F250 i used in my fleet of work trucks. With this truck there was a bad ground wire on the chassis that was for the fuel selector  so my $.02 is for you to check ground wires for the switch and the fuel tank selector valve
Bob