What are the types of car engine oil?

[Andrew]

Car engine oil is divided into: 1. Conventional mineral oil; 2. Semi-synthetic oil; 3. Full synthetic oil. Car engine oil, also known as engine lubricant, serves to lubricate and reduce friction, assist in cooling, seal against leaks, prevent rust and corrosion, and provide shock absorption for the engine. The method for changing engine oil is: 1. Use a jack to lift the vehicle, locate the drain plug, and unscrew it to drain the oil; 2. After removing the oil filter, place a container beneath it; 3. Replace with a new oil filter and add new oil. Precautions for using engine oil include: 1. The oil level should be slightly below the mark on the dipstick, as engine oil is crucial for the engine, bearing the dual functions of lubrication and heat dissipation; 2. Choose engine oil with different viscosities based on the engine's operating conditions. Use lower viscosity oil in colder seasons and higher viscosity oil in warmer seasons.

[DiJayce]

When it comes to engine oil, it's actually categorized quite specifically. Mainly divided into three types: mineral oil, semi-synthetic oil, and full synthetic oil. Mineral oil is directly refined from petroleum as base oil, with low cost but average protection and lifespan. Semi-synthetic oil is mineral oil blended with synthetic components, performing better than mineral oil with more stable performance during cold starts and high temperatures. Full synthetic oil is the premium option, entirely artificially synthesized base oil that provides instant lubrication upon engine start, especially suitable for turbocharged engines or vehicles frequently used for long-distance driving. Additionally, there are classifications by grade, such as SP, SN, etc., where later letters indicate higher standards. Remember not to just look at the brand, but also check if the specifications meet your vehicle's manual requirements.

[HopeAnn]

Choosing engine oil depends on your car's condition and driving habits. In terms of viscosity, there are grades like 0W-20 and 5W-30. The number before the W indicates low-temperature fluidity, while the number after represents high-temperature viscosity. Older vehicles might need higher viscosity oil like 5W-40, while newer cars commonly use 0W-20. Based on usage scenarios, there are long-life, fuel-efficient, and high-performance types. For example, track enthusiasts often use ester-based full synthetic oils. Diesel and gasoline engines require different oil formulations, with diesel oils labeled with a C (e.g., CK-4). During my last maintenance, I noticed the oil cap had a dexos1 certification, and the mechanic mentioned oils with this label are better matched for GM vehicles.

[ZacharyAnn]

Engine oil classification primarily depends on base oil quality and additives. Mineral oil undergoes a simpler refining process with more impurities, recommended for changes every 5,000 km. Semi-synthetic oil is an improved version of mineral oil, safer to change at 7,500 km intervals. Fully synthetic oil has the most uniform molecular structure, capable of lasting 10,000 km. API ratings are also crucial; for instance, the mainstream SP grade offers better protection against low-speed pre-ignition and timing chain wear. European cars often recognize the ACEA standard, such as A5/B5. Additionally, oils bearing the ILSAC GF-6 logo on the back are particularly friendly to vehicles with start-stop functions, preventing oil film rupture.

[VonColin]

Engine oil is like human blood, divided into different 'blood types'. Base oils are categorized into five groups: from the most common Group I mineral oil to Group V ester-based full synthetics. The ones we encounter most frequently are Group III base oils (such as the full synthetics produced by Shell's GTL process) and Group IV PAO base oils (represented by Mobil's flagship products). Nowadays, many premium oils use a blend of Group III, IV, and V formulations, significantly reducing the knocking sounds during cold starts. Japanese cars consume 0W-20 like water, while German cars often require 5W-40. Recently, hybrid-specific oils have emerged, demanding higher insulation properties for electric motors, showcasing how rapidly the technology is evolving.

[RuthAnn]

The simplest way to distinguish engine oil is by looking at the packaging. The container will be labeled with 'Synthetic Technology' or 'Full Synthetic'—full synthetic is the most expensive but has a longer oil change interval. Paying attention to the SAE viscosity number is especially important; using the wrong viscosity in winter may cause starting difficulties. Remember, turbocharged vehicles must use full synthetic oil, while naturally aspirated engines can get by with semi-synthetic. During my last maintenance, I was recommended molybdenum additive oil, which supposedly reduces metal friction noise, and indeed, the engine noise decreased slightly. It's advisable not to blindly switch to higher viscosity oil; for example, using 40 viscosity in a new car may increase fuel consumption—always follow the manual.