loud clunk w/braking help

a friend of mine has a 1997 grand am and when you apply the brakes it makes a loud clunk that you can feel thrugh the floor when you release the brakes it clunks again it sounds like it is in the rear wheels im trying to fix her car by tonight so any help will be greatly appreacated

I wish I could be more of help but its funny you mention that b/c my 99 Grand Am does a similar thing. I start the car and let it warm up for a minute then after I back out and put it into drive, I take my foot off the brake and just as I start rolling forward I hear a similar clunk noise from the rear wheels but it doesn't do it all the time. Please let me know if you figure it out b/c I probably have the same problem...I really should take it in for an inspection but I can't right now....Thanks and good luck

Hmm...can't help you.....but I think I have a similar problem here with my '96 Grand Am. I only notice it in the morning after it's been sitting all night, I back out of my parking spot, drive slowly through the parking lot, and the clunk usually happens right when I start to hit the brakes to stop before pulling out of the parking lot. It sounds like it's coming from the rear but I can't tell which side. I rarely hear the noise again for the rest of the day...typically just that one time in the morning. Anyone have any thoughts on this?

I would inspect the control arms on the rear of the car, i've heard its common for the bushings to go out, or have problems with the mount on the body. If your sure its coming from the rear of the car start there, if its coming from the front i'd look at the top of the strut towers, i've heard of simular problems with the bearing on the top of the strut. good luck and keep us posted with the results, it may help someone else find their problem.