How often should oil be changed for infrequently driven cars?

[VonBriella]

For infrequently driven cars, the oil should be changed every six to eight months. The method for changing the oil is as follows: 1. Lift the car, remove the underbody panel, and place a container under the oil drain plug. 2. Unscrew the oil drain plug, use an air gun to blow for two minutes at the oil filler port, then tighten the drain plug after draining and wipe it with a tissue to check for leaks. 3. Reinstall the underbody panel, lower the car, and add new oil through the oil filler port. The functions of engine oil are: 1. To separate the surfaces of relatively sliding parts, thereby reducing wear. 2. To carry heat back to the oil pan and dissipate it into the air, helping the radiator cool the engine. 3. To circulate carbon deposits, sludge, and worn metal particles from engine parts back to the oil pan, flushing away contaminants generated on the working surfaces of parts through the flow of the lubricating oil.