One problem related to engine has been reported for the 2008 Ford F-550. The most recently reported issues are listed below.
The contact owns a 2008 Ford F-550. While driving 70 mph, the vehicle lost power and the speed immediately decreased to 15 mph. There were no warning indicators. The contact pulled over and the vehicle was towed to the dealer. The dealer was unable to determine the cause of failure, however, they had to replace the wire harness to restart the vehicle. The current mileage was 18,000 and failure mileage was 16,000.