When I push the break my Passat makes a hard knocking sound. Someone told me it could be the control arms, but after doing some research, it just doesn't seem right
My car has 139246 miles.
Your friend could be right. If you hear a single knock each time you hit the brake pedal, that could be rear control arm bushings shifting. It could also be motor mounts. If you are hearing a knocking that repeats about the speed of the wheels turning, you may have a warped or cracked brake rotor. In either case, you should have it checked out to be sure it isn’t something about to fail catastrophically. You can do that without leaving home by contacting Your Mechanic. They will send a technician to your home or office to check out your knocking noise and let you know what it needs to fix it.