2003 Ford F-250 Super Duty Q&A
2003 Ford F-250 Super Duty Question: pulling a 5th wheel up hill
Whereas there are dozens of things to be aware of with this engine, focusing on your symptom, I'm wondering if the fan clutch is sticking on unnecessarily. The fan clutches in the early 6.0L equipped trucks could fail. - DaveJHM
A severe lack of power may develop because the hose from the turbocharger to the intake manifold can come loose, resulting in loss of boost pressure to the engine.