President Donald Trump paused most reciprocal tariffs on trading partners for 90 days, but sectoral tariffs, such as those on vehicles, still apply.
Edmunds said this decline showed a consumer flight to longer loans.
CEO Ho Sung Song tells investors Kia wants to eventually sell 90,000 electric pickups in North America as the South Korean automaker downgrades its EV sales outlook.
The market grew 4.4 percent to 3.9 million in the first quarter, driven by hybrids and light trucks. Among automakers, GM, Hyundai and Nissan were big winners, while Ford, Stellantis, Tesla and Toyota lost share.