Some 2017-2018 F-150s built on or before 10-Jul-2018 and 2018-2019 Expedition and Navigator built on or before 8-Apr-2019 with 3.5L EcoBoost may exhibit tick, tap, or rattle type noises from top of engine front cover for 2-5 seconds after a cold start. A TSB is expected to be published late 4th quarter 2019. In the interim, replace all 4 VCT units and update the PCM calibration. Do not replace other cam drive related components unless inspection identifies a concern. Refer to the Workshop Manual (WSM), Section 303-01. Claim labor replace VCTs using published labor operations and PCM programming using M-time. Part availability is currently limited. Dealers should order parts only when required to complete a repair. Once the parts are ordered, the vehicle may be returned to the customer to drive. This condition does not affect long term durability or performance.