[superdutynick]

While poking around I found this (6.0 PowerStroke bulletins), which might explin things.

2003/04 Computer Programming Recall 06E17:
Truck built before 9-29-03 are being recalled to have the computer reprogrammed. The reason for this recall is to correct fuel injection timing during cold operation, EGR valve control, lack of power, check engine light illumination (P02263 or P0299), hard starting and rough running concerns related to Exhaust BackPressure sensor corrosion. Other symptoms not listed in this recall, but which could occur, would be excessive smoke, turbo control and surging at idle or cruise. The new update eliminates the EBP sensor input to the computer. The exhaust backpressure will now be inferred/calculated using other sensor signals. Trucks should be reprogrammed using versions 41.8 or 42.1 or higher.
After this reprogramming, the truck should be test driven, the computer checked for a codes and the codes cleared (even if none are present), the key cycled on for five seconds, then turned off twice, then the engine started and allowed to idle for 5 minutes at operating temperature to allow the computer to relearn the EGR valve closed position value. This is to prevent erronious codes or driveability sysmptoms related to the EGR valve an turbo performance. Broadcast Messages 5452, 5529.
You should notice an increase in turbo cycling closed/whistling at idle and at stops. This is normal, and is to help keep the variable vanes from sticking.

So Ford was having probmles with the EBP and decided to ignore it?