95 Mustang GT steering wheel shake when braking

Most of the time when applying the brakes, the steering wheel will shake, or the car will shake. Even sometimes, the car/steering wheel will not shake at all. Normal braking is applied in both situations. The mechanics say the rotors look perfectly fine and not warped, and the brake pads were changed (didn’t solve the problem). I’m just really confused why this shake doesn’t happen all the time, only most of the time. The alignment is as good as it’s going to get without getting a camber kit, even though it’s just SLIGHTLY off. I don’t think that is the problem. Any further ideas? Thanks

If the rotors are indeed true (measured, not simply visually checked), sounds like there is some slop in the linkage somewhere, or the alignment needs another look. Tie rod ends? Steering? Loose lug nuts? Warped wheel due to overtightning? Damaged wheel from having hit a pothole or curb?