I would suggest you use the "New Formula" Mobil1 Syth ATF available at Wal-mart for ~$6 qt. It lists fully compiable with Kia SP-III on the bottle and is a far better fluid than the OEM fluid. If you are doing a trans service yourself, just do a full drain and fill (3x) and use the new Mobil1 fluid each time you top off the exact amount you drained out. Remember to drive around (up to highway speeds) between drain and fills to better remove the old fluid concentration. You will be greatly pleased with the shift quality you get. To best get this result you can also remove for 10 min the fuse in the underhood fuse block to reset the transmission computer which "remembers" the driving style and shift points (after the third drain and fill). With the new fluid, you want the computer to "relearn" with the new fluid installed. Good luck.
transmissiom fluid for 2001 kia optima 4 cylinder
WE recommend 5W30
or mopil xhp that's very good the 2003 kia optima uses 5w-30
V6 L14459 or PH9688
5-20
Sp ii sp iii
specs call fro spIII trans oil, can also use castrol multi-import.
The 2002 Kia Optima runs on regular unleaded.
The 2008 Kia Optima runs on regular unleaded.
The 2006 Kia Optima runs on regular unleaded.
The 2003 Kia Optima runs on regular unleaded.
The 2007 Kia Optima runs on regular unleaded.