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RecallGazette

Vehicle problems, recalls & safety intelligence

Ford F-150 2017–2020technical service bulletin

Bulletin 21N03 · NHTSA communication 10189762 · issued Mar 2, 2021

Technical service bulletin
communication type
Engine and Engine Cooling
component
2017–2020
model years
4
vehicle entries

Official summary

Certain 2017-2020 Model Year F-150 Equipped with a 3.5L GTDI Engine Cam Phaser Replacement In some of the affected vehicles, an undesirable noise may develop from the cam phasers in the 3.5L GTDI engine. This noise might occur as a rattle when starting the engine after the vehicle was turned off for an extended period of time or as a knocking noise when the engine is idling after it is warmed up. A cam phaser that has developed an undesirable noise does not affect the vehicle safety, performance, or emissions

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.