While watching You Tuber's with 2018 mustangs reporting engine Ticking, tapping and some engines blowing up, I decided to listen to mine after and oil change. I heard what sounded like loose change in your pocket coming from the bottom of engine. The sound was intermittent but did not sound like something that should be there. Made and appointment with Ford dealer near me. They took it in on OCT. 1. after a few days they called and said they located the sound and got permission from Ford to take the engine out and pull the heads. They found cylinder wall scoring on cylinders 6 and 7 on one side. They didn't bother to check the other side because that was enough to warrant a new short block. They installed (supposedly a NEW short block). They had the car about 23 days. I have put on about 200 miles, I am going to drive it for about another 1000 miles to see if the problem comes back. There are A LOT of the same problems reported on YOU TUBE by 2018 Ford Mustang owners. Some say the dealer says the noise is normal. My dealer took care of the problem quickly i believe. Also told me I was the Forth engine they had to do that to. I believe this is a huge problem but Ford is not going to acknowledge it.