I have a 99 cavalier. When I apply my brakes to come to a stop when I first start off driving, there is a loud clunking noise in the rear. The car shakes and sounds like it is going to fall apart and has a hard time stopping. It seems that it may be happening more in the cold, but I may be wrong with that. When I pump my brakes before I drive it seems to help the noise go away a little bit. It is deffinelty coming from the rear. What would cause this loud noise?

 

It could be several different things. Have you checked your tires to make sure they are inflated properly? Also are they balanced and the treads good? You might want to check your knee assembly and make sure that there is no play in it(give it a good wiggle side to side). The stopping could be brake related. Check the brakes and make sure they are good. How is the play in your brake pedal?