2005 Avalanche Headlight issues

That sounds like a resetting circuit breaker of some sort heating up and then resetting when it cools down. Obviously I barely know what I'm talking about here, but my point is that there more components than just a switch and lights. Find an electrical schematic for the truck and see what other components are there that might be at fault. With that said, this sounds like a simple problem than a shop specializing in automotive electrical can probably pinpoint quickly and repair.

Thanks. It does act like something overheating. I jave installed breaker switches in some of my cars and trucks just to get rid of fuses but I've never seen any that come from the factory with them. But who knows. These avalanches seem to have come with electrical gremlins factory installed.