The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal ticking sound coming from the vehicle while idling. There was no warning light illuminated. The vehicle was taken to an independent mechanic to be diagnosed. The contact was then notified of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was not made aware of the issue. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 33,000. VIN tool confirms parts not available.