The transmission filter in your Kia Optima removes particles from the transmission fluid that might cause damage to the internal transmission parts and premature transmission failure. Replacing the transmission filter and fluid is a maintenance project that should be performed about every 30,000 miles to keep the transmission protected and last longer. This project can be completed by the average home mechanic in a couple of hours using basic hand tools.
Place wheel chocks behind the rear wheel and set the parking brake. Raise the front of the Kia with a floor jack positioned under the front sub-frame. Place jack stands under the sub-frame and lower the car onto them. Remove the floor jack and slide a drain pan under the car.