Engine maintenance: Importance of oil filter replacement and viscosity selection

Proper engine maintenance requires attention to both oil quality and filter condition. While changing motor oil is a routine service, failing to replace the oil filter can compromise the lubrication system. Even if a filter appears intact, its capacity to trap contaminants like metal particles and combustion byproducts is limited. Using an old filter with new oil means the fresh lubricant is immediately exposed to accumulated impurities.

Regarding oil viscosity, substituting one grade for another, such as replacing 5W-30 with 5W-40, depends strictly on manufacturer specifications. While both share the same cold-start viscosity (5W), they differ in operating temperature viscosity. A higher number indicates higher viscosity at working temperatures. Drivers should consult their vehicle manual and check standards such as SAE, API, or ACEA to ensure any substitution meets the specific technical requirements of the engine.