It’s both a truck and an SUV, but to get it accurate, your Avalanche is actually called a sports utility truck. This half-truck-half-SUV creation made its debut in 2001 and the release of its final variation, the Black Diamond Edition, closed out its production in the 2013 model year. The 2003 Avalanche 1500 came with three V-8 engine options and all three had the same procedure for replacing the serpentine belt or air-conditioner compressor belt. Replace the belts any time you notice excessive cracks, missing rubber chunks or fraying. This straightforward process requires only basic tools and a little bit of mechanical know-how.
Items you will need
- Breaker bar
- Inch-pound torque wrench
- Wheel chocks
- Floor jack
- Jack stands
- Torque wrench
Serpentine Belt Removal
Check under the hood for a belt routing diagram. If there is not one available, draw a diagram of how the serpentine belt routes around the accessory drive pulleys on the front your Avalanche’s engine with a piece of paper and a pen.
Loosen the hose clamps on each end of the air filter box outlet hose, using a ratchet and socket. Find the clip on the outlet hose that secures the upper radiator hose in place and press it downward to release it from the outlet hose. Pull the outlet hose from the throttle body – the end closest to the engine -- and the mass air flow sensor tube. Pull the outlet hose from the engine compartment.
Find the serpentine belt tensioner pulley near the top of the engine on the passenger side. Connect a breaker bar and a socket to the bolt in the center of the pulley, and rotate the breaker bar clockwise to relieve tension on the belt. Slide the belt from under the idler pulley, which is the pulley next to the tensioner pulley, then slowly rotate the tensioner counterclockwise to its resting position. Pull the belt from all of the pulleys and out of the engine compartment.
Proceed to the section titled “Air-Conditioner Compressor Belt Removal” if you are replacing the air-conditioner compressor belt.
Serpentine Belt Installation
Install the air-conditioner compressor belt first, by following the process outlined in the section titled “Air-Conditioner Compressor Belt Installation” if you removed it.
Route the new serpentine belt over all of the accessory pulleys except the idler pulley, using the belt routing diagram under the hood or your hand-drawn diagram as a reference. Rotate the belt tensioner clockwise with the breaker bar and socket, then slide the belt under the idler pulley. Allow the tensioner pulley to slowly rotate counterclockwise until it holds tension on the belt.
Verify that the grooved side of the belt is fully seated in the grooves on all the engine pulleys. Start your Avalanche’s engine and verify that the belt does not wobble on the pulleys as the engine runs. Then shut the engine off. If the belt wobbled, remove and reinstall it, then recheck it. If the wobbling persists, you may have a bent or warped pulley.
Align the notch on the throttle-body end of the outlet hose with the tab on the throttle body, then press the hose into place. Press the flexible end of the hose onto the MAF sensor tube. Press the upper radiator hose-retaining clip back into place on the outlet hose, then tighten the two outlet hose clamps to 65 inch-pounds with an inch-pound torque wrench and socket.
Air-Conditioner Compressor Belt Removal
Remove the serpentine belt by following the procedure outlined in the section titled “Serpentine Belt Removal.”
Slide wheel chocks under the backside of the rear tires and lift the front of your Avalanche with a floor jack. Position jack stands under the vehicle’s frame rails, then lower the jack until only the jack stands support its weight. Remove the jack.
Hold the engine shield – the cover under the front of the engine – with one hand and remove the five bolts securing the engine shield with a ratchet and socket. Lower the engine shield to the ground, exposing the air-conditioner compressor belt.
Find the air-conditioner compressor belt tensioner pulley between the compressor and the crankshaft pulley. Insert the square end on the breaker bar into the square hole near the end of the tensioner and rotate the breaker bar clockwise to release the tension from the belt.
Pull the belt from the compressor pulley and allow the tensioner to slowly rotate back to its resting position. Pull the belt off of the crankshaft pulley and from the engine compartment.
Air-Conditioner Compressor Belt Installation
Route the belt around the set of grooves closest to the engine on the crankshaft pulley, then rotate the tensioner pulley clockwise with the breaker bar and socket, and hold it. Route the belt around the compressor pulley and allow the tensioner to slowly rotate back toward its resting position until it holds tension on the belt.
Verify that you seated the belt fully inside the grooves on the pulleys. If the belt is not centered inside the grooves, remove and reinstall it.
Lift the engine shield back into place under the front of the engine and hand-thread the five retaining bolts. Torque the bolts to 15 foot-pounds with a torque wrench and socket. Raise your Avalanche from the jack stands with the floor jack and remove the stands. Lower the truck to the ground.
Reinstall the serpentine belt by following the procedure outlined in the section titled “Serpentine Belt Installation”
- ProDemand: 2003 Chevrolet Avalanche 1500 Serpentine Drive Belt Removal & Installation
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