One problem related to manifold/header/muffler/tail pipe has been reported for the 1996 Ford F-450. The most recently reported issues are listed below.
When applying the brakes with a load on the truck, the front brakes locked up and the rear brakes are ineffective. Dealer has seen 3 times. Dealer adjusted brake proportioning valve to maximum setting and removed the factory installed toggle which partially alleviated the problem, consumer stated that Ford motor company would not cooperate. Also, front brakes prone to lock up when apply brakes on wet or soft footting under normal road conditions, consumer states that there is a cold start exhuast manifold leak.