Ford Expedition 2017–2020 — technical service bulletin
Bulletin 21B10-S2 · NHTSA communication 10201088 · issued Jul 31, 2021
Technical service bulletin
communication type
Engine and Engine Cooling
component
2017–2020
model years
10
vehicle entries
Official summary
It may be possible that 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 your 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.
Vehicles covered
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.