Thanks to its quality and lowest price it also turned out to be the best seller. In 1986 Hyundai sold more than 160,000 cars, rising to 260,000 the following year. Now Hyundai has firmly established itself as a strong competitor in the automotive industry. The Hyundai Sonata was the next car introduced in 1988. This model was not very successful in the United States, however Hyundai currently produces 4,000,000 units per year. Hyundai has revamped them by investing heavily in the quality, research, design and manufacturing of its vehicles. As a result of this, Hyundai launched the first proprietary gasoline engine along with its own transmission, including the alpha 4-cylinder. Hyundai has introduced a 10-year or 10,000-mile warranty for all cars sold in the United States. This introduction led to the creation of the brand image and made more and more customers choose Hyundai cars over others