Ford F-150 (2009-2014) :: 2011 - Squelching Belt Upon Startup

I've got a 2011 F-150 FX4 Supercab with the 5.0L.

I've noticed that very seldom when starting it up, something under the hood squelch's very briefly. The trucks got 3019.0 miles on it as I write this letter. The actual noise itself come's and goes in less than 1/2 a second, and the trucks only made this noise 3 times during the 3000 miles I've owned it, and all the times have been fairly far apart.

I was wondering if this would be cause for concern? My old 1990 F-150 use to do this, but its issue was the bearings going out in the alternator. With only 3000 miles on my new truck the bearings should be a non-issue. Everything should be a non-issue for that matter. I'm not actually all that concerned about it, as I said in 3000 miles its only happened about 3 times...So once every thousand miles or so. And as I said the noise comes and goes in less than a second, and truck always runs just fine. Its never driven any differently.

Could this be attributed to all the heat we have been having lately? I live West Texas and right now 105 to 110 degree days are pretty much the norm, and have been for almost 2 months now. Could the excessive heat cause any to screech like that? And of course the truck has not been overheated, nor has it shown any signs of overheating.