What color indicates the need for an engine oil change?
1 Answers
Car engine oil should be changed when it turns brown and loses its translucency. Freshly added engine oil is golden yellow in color, and typically contains detergent dispersants that clean off the varnish film and black carbon deposits adhering to the pistons, dispersing them in the oil to reduce engine deposits. Engine oil, motor oil, or engine lubricant is a substance enhanced with additives in base oil, primarily containing anti-wear additives, detergents, dispersants, and multi-grade oil viscosity index improvers. The main functions of engine oil are to reduce friction and wear on moving parts, and to remove sludge (one function of dispersants) and varnish (function of detergents) from the engine.