Engine oil color reveals its age, contamination level, and operating condition. Fresh oil is amber or light brown. Oil darkened to black but still translucent after a few thousand miles is normal.

Engine oil turns black from a combination of combustion byproducts, heat oxidation, and detergent additives suspending carbon particles in the fluid. Black oil is not automatically a sign of a problem ...

Most people are familiar with the importance of oil for the internal combustion engines that power our modern vehicles. The petroleum-based fluid is designed to provide lubrication to the vast amount ...

DETROIT -- An inexpensive device that checks the condition of engine oil and warns the driver when it's time for an oil change could help Volkswagen of America Inc. and the Chrysler group avoid future ...