The original engine oil specification for the Kia K5 is 5W-30, with options for full synthetic oil, SM or SN grade. The oil capacity is approximately 4 liters. For later maintenance and oil changes, you can choose brands such as Mobil, Shell, Castrol, or Total. The viscosity of engine oil changes with temperature, so special attention should be paid 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 temperatures as low as -30°C. The smaller this number, the better the low-temperature fluidity, allowing smoother cold starts for the car. The latter number represents the oil's kinematic viscosity at 100°C. A higher value means the oil can maintain its viscosity index better at high temperatures, which can also be understood as providing better lubrication performance under high-temperature conditions. The method for changing the engine oil in a Kia K5 is as follows: Wait for the engine temperature to cool down, allowing the oil to flow back into the oil pan. Use a wrench to loosen the drain plug and place an oil pan underneath to catch the old oil until it stops flowing. Start the engine for about 30 seconds to allow the oil in the main oil passage to drain out. Use a specialized wrench to remove the oil filter. Apply some new oil to the seal of the new oil filter and tighten it clockwise by hand. Add the new oil through the oil filler cap on the engine valve cover, usually filling about three-quarters of the oil container. Start the engine and let it run for 5 minutes, checking for any leaks around the drain plug and oil filter. If leaks are found, perform necessary repairs. After stopping the engine, pull out the oil dipstick to check that the engine oil level is within the standard range.
