Mercury vibration warning switch

A drive line assembly comprising:

• a drive line including a shaft defining a longitudinal axis;
• a mercury switch located along said shaft such that said mercury switch is tilted relative to said longitudinal axis to prevent activation of said mercury switch by a radial acceleration of said drive line, said mercury switch activatable by a predetermined longitudinal acceleration of said shaft indicative of a predetermined vibration in the longitudinal direction during operation of said shaft;
• a controller in communication with said mercury switch said controller operable to identify activation of said mercury switch during operation of said shaft;
• and
• a warning device in communication with said controller, said warning device activatable by said controller in response to said mercury switch activation.

A method of detecting a vehicle drive line vibration during operation of the vehicle comprising the steps of:

• (1) attaching a mercury switch to said drive line, said mercury switch activatable by a predetermined vibration in the longitudinal direction;
• (2) identifying activation of said mercury switch;
• and
• (3) activating a warning device in response to said mercury switch activation.