'05 LOUD sqeual. tensioner or belt?

[celica91]

Corolla started making a squealing noise. replaced alternator because i have an explorer that lost its alt bearings a few weeks ago and was making the same noise. Noise stopped on the corolla for the length of my test drive after alt replacement. Wife took the car a couple days later and said the squeal is back and louder than ever. Searched this froum and noted people have had trouble with both the tensioner losing tension and just the belt. Money is tight so is there a way to test so i know which to replace next? FYI the belt looked fine when i had it off.. has about 20,000 miles of wear on it, but no cracking, missing chunks etc.

[KILLACAMNY]

Most likley the tensioner. I've been replacing belts once a year since for my wife's 05 S cuz of the squeak. Eventually, tensioner started knocking a bit and decided to replace entire thing. No problems ever since. They have updated the tensioner assembly (redesigned).

Your alternator was probably fine.