The theory was formulated in the 1960s and 1970s as new information was obtained about the nature of the ocean floor, Earth's ancient magnetism, the distribution of volcanoes and earthquakes, the flow of heat from Earth's interior, and the worldwide distribution of plant and animal fossils.
Loose or worn out tie-rod ends can be the cause of death wobble. To test them, jack up one tire at a time grab the tire at the three oâclock and nine oâclock positions, then try to turn the tire back and forth by alternatively pushing and pulling on the tire. Any movement indicates warn out tie-rod ends.
A frequent cause of squashy brakes is a misaligned calliper, causing the pads to strike at an angle. The springiness of the steel disc as it is straightened between the pads is what you then feel through the lever.