Kia's midsize sedan is based on the 2005 Hyundai Sonata produced by Kia's corporate parent. A redesigned 2006 Sonata went on sale in spring 2005. Sharing the '05 Sonata's 4-cyl and V6 engines, Optima comes in LX and EX models. With the 4-cyl, manual transmission is standard and an automatic, with a manual-shift feature optional. The V6 comes with automatic only. Front side airbags are standard. All Optimas have 4-wheel disc brakes, but ABS is optional only with the V6. V6 models have 16-inch wheels; the 4-cyl models have 15s. Optima does not offer Sonata's traction control or antiskid system.