How do I remove the headliner from 2004 GMC Sierra extended cab?

SOURCE: How do i remove the headliner board from gmc

You remove any of the trim that is contacting the headliner,remove light in the center,remove visors and any hooks that are there to hang things on ,Most of your trim has push in retainers handles and hooks,seat belts should have screws inthem.

SOURCE: i purchased a 2005 gmc sierra 1500 extended cab.

Mkisner, I have a 2003 gmc 1500 extend cab. I hear a small fan running in the headliner. It's very loud when cold outside. When I press on the grille in the head liner it quiets down. After the cab warms up the sound goes away. I ask the mechanic at the dealer what in heck is that. He said it's a fan that registers inside temperature for the air/heater. They have to take the headliner down to change it. He said expensive to change because of labor so I live with it. That is the explanation that was given to me. It does look like a speaker. The On-star voice receiver is in the mirror and speakers are the radio. That's why the radio music mutes when talking to On-Star or using the truck phone. You might what to know that Verizon has a deal with On-Star to add the truck phone to you Verizon bill for $9.95 per month sharing your minute with your cell phone. Verizon will assign a new phone number for your truck. It works great and you can program voice commands for the phone. Very powerful and clear. You can't go wrong but you have to keep On-Star active. Ken

SOURCE: I have a 2004 GMC Sierra extended cab. When I put

No switch as far as I know, but don't fill up with the engine running (if you do that) likely you have a purge/vent valve that is hanging up in the evap system.