South Korea's Hyundai Motor posted a surprise 5.5 percent fall in quarterly net profit, missing forecasts, as record car sales were dented by the impact of a stronger local currency and the cost of compensating drivers in North America for overstated fuel-economy claims.

The South Korean automaker, ranked fifth in global sales with affiliate Kia Motors, reported October-December net profit of 1.89 trillion won, down from 2 trillion won a year earlier. That compares with a consensus forecast of 2.15 trillion won in a Reuters poll of 15 analysts.

Hyundai, which has enjoyed strong sales growth in recent years by offering stylish, yet affordable models such as the Sonata and Elantra, sold 1.23 million vehicles in the fourth quarter, up 11 percent from a year earlier.

Shares in Hyundai Motor touched a four-week high on Wednesday, but are among the worst performers in the global autos industry with a 10 percent drop in the last four months. Over the same period, shares in Japanese rival Toyota Motor have gained 30 percent - a reflection of the recent shifts in the two economies' currencies.