To find it, you'll need to:
1. Identify your transmission type: Check your owner's manual. This is the most reliable way to know if you have an automatic or manual transmission.
2. Locate the transmission: The transmission is usually located towards the bottom/rear of the engine compartment, and usually fairly low to the ground. It's a large, usually metal, housing.
3. Look for the drain plug: Once you've located the transmission, look for a bolt (usually a slightly larger bolt than others in the area) near the bottom. This will be the drain plug. It may be magnetic to catch metal shavings. Be careful, it will likely be very hot if the car has been driven recently.
4. Consult a repair manual: A repair manual specific to your 2003 Kia Optima will provide diagrams and precise locations. This is the most accurate way to find the plug.
Warning: Working under a car can be dangerous. Use jack stands, not just a jack, to support the vehicle. Wear safety glasses. If you're not comfortable doing this yourself, take it to a mechanic.
