What are the types of lubricating oil?
2 Answers
Lubricating oil models are classified as: 0W, 5W, 10W, 15W, 20W, 25W. Low ignition energy causing vibration: When the engine temperature is too low, both fuel and lubricating oil are cold. During cold starts, a richer air-fuel mixture is required, which in turn demands higher ignition energy. Excessive spark plug gap or aging ignition coils and high-voltage coils can reduce ignition energy, leading to vehicle vibration. Incorrect air-fuel mixture ratio causing vibration: During cold starts, significant errors in signals from certain engine sensors or some sensors can lead to ECU miscalculations. This results in inaccuracies in fuel injection timing and ignition timing control, causing engine vibration. Uneven cylinder conditions causing engine vibration: In multi-cylinder engines, large variations in ignition energy among cylinders, along with differing degrees of piston and piston ring wear leading to inconsistent compression ratios, can cause uneven engine power output and result in engine vibration.
I've been driving for almost 20 years and encountered various lubricant issues. The model mainly depends on two sets of codes: SAE viscosity grade and API quality standard. SAE refers to numbers like 5W-30, where the number before W indicates low-temperature fluidity (0W is more cold-resistant than 5W), and the number after represents high-temperature viscosity. API grades are denoted by letters like SP, SN, with later letters indicating newer standards. Older cars often use 10W-40 mineral oil, while newer cars mostly use 0W-20 full synthetic. I remember once using the wrong viscosity for a friend's old Buick, and the engine sounded like a tractor. Always check the owner's manual first when selecting oil—don't trust random online recommendations. If temperatures drop below -20°C, it's best to use oil starting with 0W. For frequent highway driving, choose higher viscosity. Genuine products have the API certification mark on the packaging—don't risk damaging your engine by buying cheap fakes.
