The first indication of trouble may be a flickering oil pressure warning lamp or a low pressure reading on a dash gauge. If the warning goes unnoticed or is ignored, the next clue that something is amiss may be valve clatter as the hydraulic lifters or lash adjusters are starved for oil and ingest air. If the motorist keeps on driving in spite of the obvious warnings and audible protests from under the hood, the next sound he hears may be rapping or knocking noises from the rod bearings—which will eventually be followed by dead silence as the engine seizes and the vehicle coasts to a stop.

All engines will lose a certain amount of oil pressure over time as normal wear increases bearing clearances. But unusually low oil pressure in an engine regardless of mileage is often an indication that something is seriously wrong and requires immediate attention. So anytime a customer complains of a low oil pressure condition, or mentions any of the symptoms that may be due to a loss of oil pressure (warning light on or flickering, low gauge reading, valve noise or bearing noise), don’t delay in investigating the cause.