The Optima was among several vehicles that lacked structural reinforcements on the passenger side to help prevent injuries in small-overlap crashes.
The 2018 Kia Optima has earned a Top Safety Pick Plus award after receiving modifications to address issues with passenger-side crash test performance.
The Insurance Institute for Highway Safety in 2016 noticed that some vehicles appeared to have more robust structures on the front driver side. The observation raised suspicion that the cars may have been narrowly engineered to perform well when put through the small-overlap crash test, which had always struck the driver side, without applying the same reinforcements to the passenger side.
"The Optima is built on the same platform as the Hyundai Sonata, whose good passenger-side small overlap rating applies to all 2016-18 models," the IIHS said in its latest announcement. "Until recently, however, the Optima differed on the passenger side."
The organization verified that the Optima's passenger-side structure is now "functionally identical" to the Sonata's, so the Sonata's passenger-side rating now applies to both models.