I forgot to mention in my post in another thread that I did replace my serpentine belt, tensioner, and both idlers when I had a little over 100,000 on the truck as a precaution. I do have two alternators which is why I have two idlers. Now I have a spare belt with me if needed.
For the record, the removed belt looked perfect with no cracking at all, but it did have 100,000 on it. As others have said, new tensioner and idlers seems like a good idea to me.
Ed
KM4STL
'06 Sierra LBZ 4x4 Crew SB, Titan 52 gallon fuel tank, TTT/Schefenacker Mirrors
'98 Suburban, 245,000 - sold 7-4-06