A predictive diagnostics system for monitoring mechanical seals. The system autonomously detects a loss of lubrication within a sliding seal interface of a mechanical seal, the system including a loss of lubrication failure mode logic module configured to monitor data sensed by one or more sensors and diagnose conditions relating to a loss of lubrication within the sliding seal interface, and a plurality of other failure mode logic modules configured to monitor data sensed by the one or more sensors and diagnose conditions relating to specific types of mechanical failures known to occur in mechanical seal systems, the loss of lubrication failure mode logic module configured to determine which of the plurality of other failure mode logic modules are activated during the diagnosis of conditions related to a loss of lubrication within the sliding seal interface.