Here's a general procedure, but always consult your vehicle's repair manual for specific instructions and diagrams:
1. Safety First: Disconnect the negative battery terminal before starting any work.
2. Locate the Tensioner: The tensioner is usually a pulley with a pivoting arm. It's typically located near the serpentine belt, and might have a visible bolt or other access point. Look for a long, thin bolt or a lever.
3. Identify the Tensioner Release Mechanism: This is the most crucial step. There are a few common ways to release tension:
* Long Bolt/Lever: This is the most common type. You'll need a wrench (often a 15mm or similar) or a ratchet to turn this bolt. Turning the bolt *counter-clockwise* (as you look at it) will release tension on the belt. You might need a wrench and a pry bar to hold it to keep it from springing back.
* Lever-style Tensioner: Some tensioners are released by pushing or pulling a lever. You may need a pry bar or similar tool to carefully push or pull on the lever to relieve the tension.
4. Release Tension: With the appropriate wrench or tool, slowly turn or push/pull the tensioner counter-clockwise (again, as seen from the front of the engine). This will create slack in the serpentine belt. It won't usually take a huge amount of force.
5. Remove the Belt: Once the tension is sufficiently released, carefully route the belt off the pulleys, starting from the loosest part.
6. Install the New Belt: Route the new belt onto the pulleys in the reverse order of removal, ensuring it sits correctly in all the grooves.
7. Re-tighten Tensioner: Once the new belt is in place, release the tensioner (allow it to return to its normal position) and check that the belt has appropriate tension. It should have a little give but not be loose. If using a bolt-type, tighten the bolt securely.
8. Reconnect Battery: Reconnect the negative battery terminal.
Important Considerations:
* Repair Manual: This is the absolute best resource. A Haynes or Chilton manual for your specific year and engine will have detailed diagrams and instructions.
* Tooling: Have the correct size wrench or socket, along with a possible pry bar for leverage.
* Caution: Be careful not to injure yourself when working with the tensioner. The spring inside is quite powerful.
* Belt Routing: Pay close attention to the belt's routing. If you don't route it correctly, it could slip or damage the pulleys.
* Engine Type: The exact location and release mechanism might differ slightly between the 4.8L, 5.3L, and 6.0L engines in the 2002 Tahoe.
If you're uncomfortable performing this repair yourself, it's always best to take your vehicle to a qualified mechanic. Improperly tightening the tensioner can lead to premature belt wear or even damage to the engine.
