One problem related to crankcase (pcv) has been reported for the 2003 Ford F-350. The most recently reported issues are listed below.
6. 0 litre diesel rough idle, dead accelerator at times, low power, excessive smoke, poor fuel milage 8 to 12 miles per gallon. Have 30,000 miles on vehicle, poor engine response when cold, engine warning light comes on, has been to selling dealer four times for repairs, re-flash of computer for updated info from Ford but problems till present! dealer has had vehicle for the past four days ,said its fixed! picked up last nite, almost did not make it home! they now have back to look at. . Have been around diesels for the past thirty years; this one is a dud!! most all problems still present, now fuel odor in crankcase, dealer did replace I. P. C. Sensor and downloaded latest calibrations to no help!.