One problem related to front suspension hub has been reported for the 2006 Ford F-150. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2006 Ford F-150 based on all problems reported for the 2006 F-150.
Loud screeching noises from the front end. It happened several times and I took it to an out of town dealership because I was over 125 miles from home. It seems a 4 year old truck with 69k miles had to have both hub assemblies replaced, both actuators and both valve assemblies. Mechanic stated that he's had to replace over 25 Ford F-150 trucks for the same defect (his words).