One problem related to engine exhaust system has been reported for the 2006 Chrysler 300C. The most recently reported issues are listed below.
Mechanic said the exhaust valve dropped in the cylinder and caused catastrophic failure, needs the complete new engine. I have replaced the oil vigorously every 4500 mile with synthetic oil. The car has 189000 miles on it and there are tons of reports that show this is very common after 100k miles.