“Clunk” noise when braking

A better place to have the steering and suspension systems inspected is at a tire and alignment shop. The people there are experts at finding the causes of noises, vibrations, and bad tire wear. Ford front-wheel-drive cars in particular have more trouble with ball joints and tire rod ends than most other brands combined, and noises should never be ignored. The outer anti-sway bar links do cause a lot of trouble, but those are not exactly a safety hazard. It is the ball joints that cause the most crashes when they separate. Ford used to use "rubber-bonded socket" joints for their outer tie rod ends and lower ball joints. Those are a ball dropped into a socket, then they are glued together with molten rubber. It is just a matter of time before turning left and right repeatedly causes that rubber to tear, then the joint falls apart. No other manufacturer ever used that design, and no aftermarket replacement is of that design.

"Moog" is the premier aftermarket supplier. They develop designs to solve problems with original designs. Even the Ford replacement outer tie rod end is superior, and has a grease fitting.

Since you notice this more when braking, do not overlook a loose front brake pad. The clue is the noise is more of a rattle, and will stop when you hold light pressure on the brake pedal. The calipers should also be inspected for worn mounting hardware. That will allow the caliper to grab the rotor when you apply the brakes, and move until it bangs against the mounting pins. This is a better suspect than ball joints. Caliper noise is quite a bit louder than ball joint noise.

For locating the causes of elusive noises, consider borrowing a "Chassis Ear" if you can find one. Most mechanics do not even know it exists, but suspension and alignment specialists use it for finding rattles and clunks. It is a set of six microphones you can clip to suspect parts, an amplifier, and headphones. You drive around while switching between the microphones, and the microphones can be moved around to locate the source of the noise.

In the first photo, it looks like the rubber boot is split. That alone warrants a closer inspection, plus, water and dirt will get in there and grind on the mating surfaces.

What you should find is the coil spring is around the strut, and the strut is bolted to the spindle. The weight of the car transfers through the strut, spindle, wheel bearing, then wheel and tire. This means no weight goes through the lower ball joint. The joint's only job is to hold the wheel in position. As such, there are forces acting on the joint when the tire is on the ground. The car must be raised off the ground, and it must be supported by the frame so there is no stress on the lower control arm. At that point, any looseness in the ball joint will be evident when you pry it down with a pry bar or squeeze it with a large Channel Lock pliers.

The second test involves sideways movement between the ball and socket. Unless that is really bad, I need a helper for this test. The way I do it is I start by grabbing the tire and turning it left and right just a little, and with little force. You will feel any looseness in a tie rod end this way. If that is okay, I do this again, but with much more force. The goal is not to actually turn the tire or move the steering linkage more than necessary, as turning the ball joint can make a good one look sloppy, but you are using the tire as a lever, and the tie rod end is a fulcrum, to push and pull on the ball joint. The person watching has to observe if the ball is moving sideways within the socket. Even if that movement is excessive, I have found that most of the time it is hard to detect that movement by feel when you are working so hard to turn the tire. It is better to have the second person helping.

You might take a look at the control arm bushings. Worn out bushings will definitely cause the clunking when hitting the brakes. If you want, take off one of the wheels and take a bunch of pictures. Post them here and we will see what we can see. In particular, get closeups of the bushings. You might also check the bolts holding the wheel hub in place and make sure that they are tight.