A characteristic of swing-axle rear suspensions . Cornering forces can act on these suspensions to lift the body of the vehicle so that the outer wheel tucks or jacks under the vehicle. When carried to the extreme, jacking forces could tip the vehicle over. Usually this is the result of a skid in which the trailer swings around dangerously and tries to overtake the cab. A safety device that keeps the vehicle from falling to the ground if the lifting jack is removed or faulty.
Most jobs require two jack stands for safety.
The 1945-54 XK 110 models are milestone cars . The 1951-54 Mark VII and '54 Mark VII M models are milestone cars . The 1954-57 KX 140 models are milestone cars . The 1956-57 Mark VIII models are milestone cars . The 1958-61 Mark IX models are milestone cars .