Hello and welcome to Just answer.com, Super mechanic here. About your vehicle.
There has been a service bulletin for that type of concern. Here is what it states.
|Brakes - Squeak Noise On Brake Pedal Application |
Bulletin No.: 08-05-22-002C
Date: April 07, 2009
Squeak Noise On Brake Apply (Remove Brake Fluid
from Master Cylinder and Refill)
2004-2007 Buick Rainier
2008 Buick Enclave
2004-2008 Chevrolet Colorado, TrailBlazer, TrailBlazer EXT, TrailBlazer SS
2008 Chevrolet Malibu
2009 Chevrolet Malibu (VIN position 11, 4 Orion MI. build with Build Date Prior to April 20, 2009)
2004-2008 GMC Canyon, Envoy, Envoy XL, Envoy XUV
2007-2008 GMC Acadia
2008 Pontiac G6
2009 Pontiac G6 (VIN position 11, 4 Orion MI. build with Build Date Prior to April 20, 2009)
2007-2008 Saturn OUTLOOK
2008 Saturn AURA
2005-2008 Saab 9-7X Supercede:
This bulletin is being revised to update model years. Please discard Corporate Bulletin Number 08-05-22-002B (Section 05 - Brakes).
Some customers may comment on a squeak noise when the brake pedal is applied or when released. This noise is normally heard when the brake pedal is slowly applied with the engine on or off, but can occur when the brake pedal is released. The noise may be isolated to the master cylinder area.
To correct this concern, remove as much of the old brake fluid from the master cylinder as possible and refill with a new DOT 3 brake fluid, P/N 88862806 (in Canada, use P/N 88862807). Start the vehicle and fully cycle the brake pedal until the noise diminishes to allow the new fluid to enter the system.