One problem related to engine knocking noise has been reported for the 2009 Ford F-150. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Ford F-150 based on all problems reported for the 2009 F-150.
Purchased this vehicle used from a well known and popular dealer in utah. We did not note any noises during the test ride and vehicle appeared in great condition. On the drive home (of course) we stopped for dinner. Noticed a loud knocking noise coming from the engine. This continued and worsened and we feared the vehicle would stall. The problem subsided when the rpm's increased slightly. We were able to duplicate the problem repeatable in a parking lot at low speeds and low rpms. Specifically when turning left and the problem worsened when the 4x4 was selected. I video taped the engine noise as proof for the dealership. Doing research we have noted that this is a common problem with the 2009 f150 5. 4 l. Range of problems described as either cam phaser or internal engine problem. Corrections have been noted as either cam phaser replacements (not very helpful) or full engine replacement. Taking the vehicle back to the dealer this morning to return.