Warped rotors
Warped rotors is the most likely cause. Have the rotors turned or replaced and new pads installed.
You have warped rotors. They will need to be removed and trued or replaced. Causes of this are lug nuts overtightened, or heat from heavy braking at high speeds.
A bad tire with belt separation. Loose/worn steering joints. Bent rim. A warped rotor (if wobble happens while braking only).
not usually. warped rotors will cause a vibration during braking.
Possible broken spring.
warped rotor
If it only happens when you are braking I would suspect warped brake rotors. Other reasons the front end could shake would include unbalanced tires or the vehicle needing realignment. Whatever the case may be; driving a car in this condition is unsafe and you should repair it or have it repaired before you drive it again.
amount of force or gravity pulling on it
Your rotors are probably warped from getting hot during braking and need to be "turned" or replaced. I suggest you take it to a brake shop or dealer.
A spiraling football will go further than a wobbling. The spiral movement will go further due to air. The spiral uses the air to move smoothly through as a wobbling football is all over the place so its actually using the air to slow down instead of moving smoothly.
rockers and neck bearings need to be checked every 2500 miles on the springers. good luck, D