What are the differences between Shell fully synthetic engine oil 5W-30 and 5W-40?
2 Answers
Shell fully synthetic engine oil 5W-30 and 5W-40 have the following differences: Different high-temperature viscosity: The difference between 5W30 and 5W40 engine oils lies in their high-temperature viscosity. 5W40 has higher viscosity, providing better high-temperature protection and sealing performance. However, higher viscosity is not always better, as excessive viscosity can negatively affect the engine. Different fluidity: Winter oil grades are: 0W, 5W, 10W, 15W, 20W, 25W. The symbol W stands for winter. The smaller the number before W, the lower the low-temperature viscosity, the better the low-temperature fluidity, and the lower the applicable minimum temperature.
I mostly drive for commuting and have used several Shell 5W-30 and 5W-40 oils. The main difference lies in viscosity at high temperatures: 5W-30 oil is thinner, provides faster cold starts, easier winter startups, slightly lower fuel consumption, and is suitable for daily city driving with quicker engine response. 5W-40 oil is thicker, offers better engine protection at high temperatures, reduces engine wear during summer long-distance drives or mountain routes, and has lower noise levels; however, it consumes slightly more fuel. Synthetic oil itself has strong cleaning power, longer oil change intervals, and saves on maintenance. It's recommended to check the car manual's suggestion: choose 30 for mild driving in cooler weather, and 40 for high-temperature aggressive driving. Don't just focus on saving money; engine health is crucial. Both are good options, and Shell's quality is reliable.
