Preventive maintenance routines involve changing oil regularly, with aging oil potentially becoming diluted and contaminated which causes engine wear to take place too soon. You should make sure that you have all the tools before beginning such as a shallow drain pan to stop spills, rubber gloves to protect your hands, a breaker bar to loosen tight drain plugs, a socket to fit the breaker bar, and a filter wrench of the correct type to your engine. Always have lots of spill rags or newspapers at hand and also keep in mind that the engine and exhaust parts are going to be hot so expect future problems. Find a flat area and park the vehicle, turn off the engine and wait for the engine to warm up so that oil can flow out of the engine. Take off the filler cap, and, when it is present, unscrew the oil filter housing to leak the oil. Lift the car safely on jackstands, then dismount the splash shield then position the drain pan beneath the drain plug and then carefully remove it. Let the old oil run and look into it to see whether there are metal shavings, and clean up the drain plug and space and place back. In certain models of the engine, place the drain pan below the oil filter, loosen and remove an old oil filter with the filter wrench and make sure that the rubber gasket on the old filter does not adhere to the housing. Wipe the gasket of the new filter with clean oil, and firmly screw it on. Pour in more oil using the filler cap, feel the level after several minutes, and then switch on the engine to circulate the oil. Having run the engine a little, check the oil level again and fill up, if required. Dispose old oil in a proper manner making sure that it is recycled and not dumped on the ground or into the drain. Lastly, turn the service indicator to an off position by pressing the buttons on the instrument cluster to have an appropriate record of the engine operating time and vehicle mileage.