Ford F-150 2017–2021 — technical service bulletin
Bulletin SSM 50445 · NHTSA communication 10207139 · issued Jan 31, 2022
Technical service bulletin
communication type
Equipment
component
2017–2021
model years
5
vehicle entries
Official summary
Some 2021 F-150 vehicles built on or before 01-Feb-2021, 2017-2020 F-150 vehicles equipped with a 3.5L EcoBoost engine, 2018-2020 F-150 vehicles equipped with a 2.7L EcoBoost or 5.0L engine, 2019-2020 F-150 vehicles equipped with a 3.0L diesel engine may exhibit a high pitched squeal or whistle type noise from the engine compartment after the engine is shut off. This condition may be due to the air conditioning (A/C) low side system pressure exceeding the high side pressure resulting in equalization of A/C system pressures through the A/C compressor. An updated A/C compressor has been released
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.