Which is better for the Buick Excelle, 5w30 or 5w40 engine oil?
2 Answers
For the Buick Excelle, it is recommended to use 5w30 engine oil. The details about engine oil are as follows: 1. According to the car maintenance manual: 5w30 is the recommended engine oil for the Buick Excelle. The 5w30 engine oil has better fluidity and superior low-temperature anti-wear performance. 2. Low-viscosity engine oil has become mainstream: Only Volkswagen vehicles still require 40 engine oil due to piston tension issues. 3. Engine oil grades: They are classified by quality grade and viscosity grade. Engine oil for gasoline engines is usually denoted by the letter "S", while diesel engine oil is denoted by the letter "C". 4. Composition of engine oil: It consists of base oil and additives, where the base oil is the main component of the lubricant, determining its basic properties, and additives can improve the shortcomings of the base oil.
I've been repairing cars for over a decade and have handled hundreds of Buick Excelle models. The choice between 5W30 and 5W40 mainly depends on your driving conditions. In northern winters with temperatures below -20°C, 5W30 offers better low-temperature fluidity, ensuring smoother cold starts and reduced engine wear. For southern summer heat or frequent high-speed/high-RPM driving, 5W40 provides superior high-temperature protection with more stable oil film integrity. For Excelle models over 100,000 km, I recommend 5W40 as it better seals enlarged piston ring gaps. New cars should stick to the manual-specified 5W30 for fuel efficiency and quiet operation. Once I switched someone to 5W40 and their fuel consumption increased by 0.5L/100km – so don't blindly opt for higher viscosity. Those planning summer mountain road trips might consider temporary 5W40 use, but it's unnecessary for daily commuting.
