What are the effects of excessively high engine oil viscosity on a car?

[MacAaliyah]

Effects of high-viscosity engine oil on a car: 1. Reduction in engine effective power: High oil viscosity increases the crankshaft's oil stirring resistance, leading to greater internal power loss in the engine. 2. Difficulty in ignition at low RPM: High oil viscosity requires more torque for crankshaft rotation during cold starts, resulting in lower RPM and difficulty in ignition. 3. Poor filter cleaning performance: High oil viscosity slows down circulation speed, reducing the number of passes through the filter and hindering timely removal of wear debris from friction surfaces. 4. Inferior cooling effect: Poor oil flow and slower circulation decrease the rate of heat removal from friction surfaces, resulting in poorer cooling performance and increased risk of engine overheating. 5. Higher carbon residue: High-viscosity oil tends to have larger carbon residue particles and higher solidification points, which can easily clog oil passages.