AC Belt braking

2000 sierra 1500 have had to replace the ac belt three times. Looking for any help. I suspect the compressor but Im not sure.Thanks

How does the "break" look? Does the belt look worn all the way around like it slipped or does it just have a clean torn break? Are you replacing the belt with a AC delco? There are some off brand belts out there not worth a $#@!. Take your belt off. Check all pulleys that are "turnable" by hand. Are they smooth and free rolling? Do they have any wobble? Looking from the side, do they look like they all line up in line. Might be able to use a yardstick to check this. I'm sure you've made sure of this but, is the belt on the right pulleys (looking at the belt diagram)?

if i'm not mistaken...that trk should have a seprate belt for ac that runs straight off the crank.
deepee might have somthing with pulley alignment or belt quality...could still be compressor locking up ... one of three...most likely compressor locking up

I am having the same problem with my 00 Sierra. The belt has broke 4 times now. The mechanic has tried several brands of belts including AC Delco. The break of the belt is a clean snap. There is only 1 mark on the flat side of the belt. It appears to be a rub mark and is about 1-2 inches in length. On the grooved side of the belt, there is a very small area in between 2 grooves that are damaged.
I have also had the tension arm replaced thinking that may have been a factor, but no difference.

I have been told that if the compressor was locking up you would see alot of wear marks on the flat side of the belt.

Also, everytime it has broke, I was driving on the highway at speeds 60 or greater. If that makes a difference. I have over 144k miles on the truck and started haveing this problem after about 120k.

This happened to me with my 2004 1500. I only had 1200 miles on it. Dealer said idler pulley locked up, took out the compressor.