How to Replace the Belt on a 2003 Chevrolet Trailblazer
- 1). Open the hood of your Trailblazer and locate the negative battery cable end on the negative battery terminal of the battery. Loosen the retaining bolt on the negative battery cable end with a wrench and then remove the cable from the battery, isolating it from the terminals while you are working.
- 2). Locate the automatic belt tensioner on the front of the engine. On the Trailblazer, the tensioner is on the front passenger side of the engine, about halfway up from the bottom. The tensioner is a long metal arm with a pulley on the end closest to the belt.
- 3). Insert a 3/8-inch drive breaker bar into the square hole on the back of the tensioner. Rotate the tensioner clockwise, releasing the tension from the belt. Remove the belt from the pulleys and discard it. Carefully rotate the tensioner counterclockwise, letting it rest in the home position.
- 4). Route the new belt over the pulleys on the front of the engine, following the path on the diagram under the hood of your Trailblazer. Rotate the belt tensioner clockwise with your breaker bar and slide the belt under it. Rotate the tensioner counterclockwise, tightening the belt.
- 5). Install the negative battery cable on the negative battery terminal then tighten the retaining bolt with a wrench. Start the engine and visually verify that the belt is running correctly over the pulleys.
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