Does the 2004 Hyundai Sonata have a timing belt or chain?

The 2004 Hyundai Sonata comes equipped with a timing belt, not a timing chain. Those did not begin to be produced until after the 2006 model Sonata. With a timing chain, You can expect it to last for the lifetime of the vehicle. However, You will need to have Your timing belt checked regularly. Every 10,000 miles or 12 months, whichever comes first, You should check the belt for wear and tear, damage or breakage. If the belt needs to be replaced, You can expect to pay up to $38 to $188 for a new one. If You choose to have the belt replaced by a professional service technician, You can expect to pay an additional $50 to $240 for labor.