Keeping your Ford Focus in good running condition means taking care of problems as soon as they arise. If you notice oil under your car, it may indicate that the oil pan gasket is worn out. Fortunately, replacing the oil pan gasket in a Ford Focus is a fairly straightforward operation. Here's how to change the gasket in a 2000 to 2004 Ford Focus.
Raise the front of the car up with jacks and stabilize it carefully on a jack stand. Put blocks ahead of the rear wheels to prevent the car from rolling.
Put a receptacle under the engine, and use a wrench to remove the oil plug from the bottom of the oil pan. Let the oil completely drain into the receptacle and replace the plug before proceeding.
Disconnect the negative battery cable and remove the catalytic converter. Loosen the bolts on the oil pan, and carefully remove the pan, using a screwdriver and mallet to loosen it, if necessary.
Scrape the old gasket away from the oil pan very carefully so you don't scratch the surface, then wipe the surface thoroughly with solvent to remove any trace of debris, and wipe out the inside of the oil pan with a dry cloth.
Allow the surface to dry, and then wipe it with a thin layer of oil to promote adhesion. Place the new gasket on the surface.
Replace the oil pan, and tighten the bolts. Replace the catalytic converter and the negative battery cable.
Raise the front of the car with jacks, carefully remove the jack stand and lower the car. Fill the crankcase with the appropriate oil to the fill level, start the car, and check the oil level one more time.