The Chevy Trailblazer is available with several different engine options but all of them use the same style belt--a single serpentine belt that turns all the accessories on the front of the engine. The belt runs over the pulleys in a specific path that must be followed when installing the new belt. A new belt is available through the Chevy dealer or an auto parts store, and the belt path is available on a label under the hood of the truck for you to reference.
Locate the negative battery cable on the negative terminal of the battery. Remove the retaining bolt from the cable end with a wrench and lift the cable off the battery. Isolate the battery cable from the battery terminal while you are working.
Locate the serpentine belt tensioner on the front of the engine. Place the square drive from a 3/8-inch drive breaker bar in the square hole in the arm of the tensioner. Rotate the tensioner clockwise, loosening the serpentine belt.
Slide the serpentine belt off the pulleys while holding the tensioner off the belt. Discard the old belt and install a new belt over the pulleys. Rotate the tensioner counterclockwise allowing it to tension the new belt as you go.
Remove the breaker bar from the tensioner, then out of the engine compartment. Inspect the belt to ensure it is on the pulleys correctly, then double-check the path of the belt against the diagram on the sticker under the hood of your Trailblazer.
Install the negative battery cable on the negative terminal of the battery. Insert the retaining bolt and tighten it with wrench. Start the engine and watch the belt to be sure it is running smooth and squarely over the pulleys.
