Should the Buick Regal use 5W30 or 5W40 engine oil?
2 Answers
The Buick Regal uses 5W30 engine oil. Differences in engine oil grades: Compared to 5W30, 5W40 has the same low-temperature fluidity but differs in high-temperature performance. 5W40 has higher viscosity, providing better high-temperature protection and sealing performance. However, the increased viscosity also leads to greater engine running resistance and higher fuel consumption. For the Regal's engine, 5W30 engine oil is more suitable. Engine oil operating environment: Naturally aspirated engines have lower requirements for engine oil and can use mineral oil or semi-synthetic oil. If the consumer's budget allows, full synthetic oil can be used. Compared to naturally aspirated engines, turbocharged engines have a more compact structure and more complex operating conditions, requiring higher-quality engine oil with better fluidity. It is recommended to use full synthetic oil for turbocharged engines.
I've been driving my Buick Regal for almost 5 years and have consistently used 5w30 engine oil. From my multiple maintenance experiences, 5w30 flows well during cold starts in winter, allowing the engine to be protected quickly, and doesn't become too viscous in summer heat to cause increased fuel consumption. The owner's manual also recommends this viscosity because it balances lubrication and protection. 5w40 is thicker and more suitable for older vehicles or frequent high-speed driving in hot regions, but for normal driving, it might increase resistance and fuel consumption. Remember to regularly check the dipstick to ensure proper oil levels. The oil change interval is typically 5,000-7,500 kilometers, which can extend engine life. Overall, I recommend prioritizing 5w30—it's worry-free, convenient, and cost-effective.
