What are the signs of engine oil deterioration?
3 Answers
Engine oil deterioration manifests in the following ways: 1. Decreased viscosity. 2. Severe water-like thinning. 3. Presence of metal shavings and sludge. The causes of engine oil deterioration include: 1. Filter malfunction; engine water ingress. 2. Poor crankcase ventilation and inadequate cooling. 3. Cylinder wear or piston ring damage; prolonged oil usage. Methods to address engine oil deterioration: 1. Change the oil on schedule. 2. Regularly inspect the oil dipstick for signs of oil deterioration. Engine oil, also known as motor lubricant, serves to lubricate and reduce friction, assist in cooling, seal against leaks, prevent rust and corrosion, and provide shock absorption for the engine.
With extensive driving experience, I've witnessed numerous cases of oil degradation. When checking the dipstick, the oil color changes from light yellow to dark brown or even black, indicating obvious oxidation; significant viscosity changes occur, thinning oil provides insufficient lubrication, leading to increased engine noise or vibration; there's also a pungent burnt smell resembling something charred, showing thermal breakdown; contaminants mixed in the oil, such as metal particles or sediment, may accelerate component wear; occasional emulsification and foaming, appearing as creamy substances, signify moisture infiltration affecting performance. I remember after a long-distance drive, the dipstick showed cloudy oil with foam, and fuel consumption suddenly increased - the repair revealed aged oil with water contamination, reminding me never to neglect regular maintenance.
As an average car owner, the most obvious signs of oil degradation I've noticed are a sudden spike in fuel consumption and worsening vehicle performance. The oil turns black and becomes sticky quickly, with reduced viscosity causing rough gear shifts; a sour or chemical-like odor is a red flag; dipstick inspection reveals particles or sediment resembling fine sand; when emulsified, milky white foam floats on the oil surface, indicating lubrication failure and engine overheating. Once I ignored these symptoms and faced costly repairs—now I've learned to act promptly when the oil darkens or shows inconsistent texture. Simple maintenance saves big money—don't wait until engine damage brings regret.
