The in-tank filter:

[Stewart G Griffin]

Just curious, does the in-tank fuel filter/(sock filter?) ever need to be changed?

[Irish_Alley]

i never heard of them being the problem but most times if someone drops the tank to replace the sock then they will be replacing the fuel pump and sock/strainer. that being said if you want a valid warranty with the electric fuel pumps then you have to replace the sock/strainer or it will void the warranty

[LTZ C20]

The intake sock filter is only changed when the sending unit or sending unit/fuel pump combo are changed. I believe the warranties on these replacement units are void if the sock is removed.

[Irish_Alley]

some sending units you can just replace the pump for $40 or replace the sending unit for $185
http://www.autozone.com/external-engine/fuel-pump/premium-fuel-fuel-pump/chevrolet/c1500-1-2-ton-p-u-2wd/1994/6-cylinders-z-4-3l-tbi/563477_478947_6210/?checkfit=true
and this is in the notes
"Notes:   Electric
Failure to install a new fuel strainer (where applicable) will void warranty"