The original engine oil for the Cavalier is Shell, with the model number 0W20. For later maintenance, you can use oils from manufacturers such as Mobil or Great Wall. You can choose oils with specifications 5W30 or 0W30. The viscosity of the oil changes with temperature, so special attention is needed to its performance under both low and high temperatures. For example, in 5W-30, the first number indicates low-temperature fluidity. 5W means it can withstand low temperatures of -30°C. The smaller this number, the better the low-temperature fluidity, making cold starts smoother. The latter number represents the kinematic viscosity of the oil at 100°C. The higher the number, the better it maintains viscosity under high temperatures, which can also be understood as better lubrication performance under high-temperature conditions. The method for changing the oil in the Cavalier is as follows: Wait for the engine temperature to drop, allowing the oil to flow back into the oil pan; Use a wrench to loosen the oil drain plug and place an oil pan to catch the old oil until no more oil flows out. Start the engine and let it run for 30 seconds to allow the oil in the main oil passage to drain out; Use a special wrench to remove the oil filter; Apply oil to the seal of the new oil filter and tighten it clockwise by hand; Add new oil through the oil filler cap on the engine valve cover, usually filling about three-quarters of the bottle; Start the engine and let it run for 5 minutes, then check for any leaks around the oil drain plug and oil filter. If there are leaks, perform necessary repairs; After stopping the engine, pull out the oil dipstick and check that the engine oil level is within the standard range.
