What does the term “sludge” refer to in engine maintenance?

The term "sludge" in engine maintenance refers to thick residue buildup from degraded oil or contaminants. Over time, engine oil can break down and lose its effectiveness due to exposure to heat, contaminants from combustion, and other environmental factors. This degradation can result in the formation of sludge, which is a gummy, thick substance that can accumulate in the engine components, including passages and filters.

Sludge can hinder the flow of oil throughout the engine, potentially leading to inadequate lubrication, increased friction, overheating, and ultimately, engine damage. Understanding the nature of sludge and its causes is essential for maintaining proper engine performance and longevity. Regular oil changes and using quality oil can help prevent sludge formation by keeping the oil clean and effective in protecting the engine.