I just got my 01 Z28 and realised there's two belts, drive belt and accessory belt. When I start it up I hear one squeaking, can't tell which one... Will replacing them both just for the heck of it cure the squeak however or is this normal every cold morning for an LS1?

 

Check to see if the belts are cracked or show signs or wearing out. Replacing them almost always stops the whine unless it's a pulley.

 

It's one of a few things..

You could replace the belts just because they're cheap and they'll need replacing sooner or later but it could be your serpentine belt tensioner. They are notorious for going bad. Mine did.

It could ALSO be your a/c tensioner pulley. Took me a year to figure out mine was bad!

Hope this helps.