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.
Just because you can't feel a lot of free play or wobble in a wheel doesn't mean there isn't enough to cause vibration. It doesn't take a lot to be responsible for objectionable vibration at speeds of 60 to 70 mph and aboveany deviation from a truly circular spin is called runout.