Hyundai's 10 year/100000 mile warranty was denied. My car ran smooth with 77,000, mostly highway miles, up until 2 days before the engine went. I did oil changes regularly, rotating my tires at the same time. Two of my tires are still original with tread left! Brakes have never gone bad because of highway miles, not stop and go. I changed to Synthetic Oil about 1-1/2 years ago. One day, I hear clicking in the engine when accelerating. Next morning Engine light stays on when I start the car and loud banging out of the engine. Never lost a drop of oil under the car and they said it was engine sludge due to lack of maintenance... refused the Warranty claim and I have a dead car with an $8000 repair bill estimate. Hyundai refuses to let me appeal saying the Corporate Office decision is "Final". Our family is devastated and Hyundai does not care one bit! Never again... after buying "8" cars from them, I feel abandoned. Hyudai/Kia are no longer on my list, my family's list, or any of my friend's list! Big Mistake Hyundai!