Headlights flickering

[Geotrash]

I am having a similar problem. Lights dim when coming to a stop or when RPM drop, crank has been sluggish recently, and my cigarette lighter is showing that when my Tahoe sit my battery only has 11.8v. My charging gauge still looks normally, varies between 12 and 15. and my battery, cables, belts, and pulleys are all under 1 year old so I don't want to start throwing parts at this thing until I am sure what the problem is. I took my Tahoe to Orileys and they tested both alternator and battery and they said both are good.

So without replacing both my battery and my alternator at the same time should I just wait until my Tahoe stops starting to start throwing parts at it?

Lights flickering noticeably is almost always a sign that the rectifier in the alternator is on its way out, in my opinion, in the absence of a large power drain like an amplifier, etc.