CAKen

Idk if this topic is dead but I have a different startup noise from the videos.. 2015 5.3L Sierra 1500. I’m in CA so it never really gets that cold, my noise is like a high pitched whine that follows the sound of the ignition at startup. Best way I can describe it is like one of those whistles my kid has with a little rotor in it... higher pitched the louder you blow. Took it to the dealer and they heard it but had no idea. They replaced my starter thinking it had something to do with that but didn’t fix.. sounds like metal on metal to me. Some tech was saying sounds like something rubbing the flywheel but it goes away after it’s at operating temp, sometimes never hear it at all, sometimes still makes the sound when it’s warm and restarting. Had it in 4 times now and nobody can figure it out.