When Should Engine Oil Be Changed Based on Its Color?
2 Answers
Engine oil should be changed when it turns black, as the darkening indicates it has cleaned out the dirt inside the engine. Engine oil, also known as motor oil or engine lubricant, is a substance enhanced with additives in base oil, primarily containing anti-wear additives, detergents, dispersants, and multi-grade viscosity index improvers. Engine oil is used for lubricating internal combustion engines. Its main functions include reducing friction and wear on moving parts, removing sludge and varnish from the engine, neutralizing acids produced by fuel and lubricant oxidation, improving piston ring sealing, and cooling the engine by carrying away heat from moving components.
Observing the color change of engine oil during car maintenance is a practical experience. Fresh oil pours out golden and transparent, but after about three months or a few thousand kilometers of driving, it gradually turns dark brown or black, signaling it's time for a change. Besides color, I also check the viscosity on the dipstick—if it feels sticky or has a gritty texture, it indicates high impurity levels, which can cause significant engine wear. Once, I forgot to check regularly and drove a long distance with darkened oil, resulting in increased engine noise and unnecessary repair costs. Now, I make it a habit to check every six months or 5,000 kilometers, sending the car for service immediately if the color looks off, combined with the intervals recommended in the car manual for extra safety. Developing this habit of early detection and action keeps the car running smoothly and worry-free.
