My 2007 Pontiac Grand Prix is making a

[Lisa]

hissing sound? It is the GXP model and for the last 2 days it makes a hissing noise while driving(almost sounds like a tea kettle). It happens randomly as I am driving and gets louder when I use the brakes. Any idea what this might be? Last time I got my brakes done was in August 2007 (at the Pontiac dealership) and 2 weeks ago they did a 100 point inspection and the brakes were fine.

 

[Goatman]

It sounds like the brake pads are screaching against the rotors , when you had the brakes done did they turn the rotors also?
if not that could be where the noise is coming from ..
even if they were done at the same time were factory pads used?
some aftermarket pads are noisy , also if the brake caliper retaining clips were not replaced correctly they can also make a noise I would suggest you have them looked at by the shop that did the work and explain you think they were not done with the proper attention to detail...