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How to Replace Serpentine Belt 02-06 Chevy Trailblazer

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  1. step : Remove the serpentine belt (0:25)
    • Locate your serpentine belt routing diagram or draw one out.
    • Use your 3/8â€? drive ratchet to loosen the serpentine belt tensioner and remove your belt.
  2. step : Install the new serpentine belt (2:41)
    • Use your routing diagram to loop the belt around the pulleys correctly.
    • Release the tension from the belt tensioner pulley to loop the belt over the last pulley

Brought to you by, your source for quality replacement parts and the best service on the internet. In this video we'll be showing you how to remove and put back on the Serpentine belt on this 2004 Chevy Blazer with a 4.2 liter. Only tools you'll need is a 3/8 ratchet and you'll want either a long-handled ratchet or a piece of pipe to get some extra leverage as well.

First thing you want to note is how the Serpentine belt is on your vehicle. It goes across up there to the alternator and down to an idler pulley and down around the AC pulley way down there, then up and around the water pump and fan and then it wraps back down and around the crank and back up to the tensioner right there. I'm going to place the camera over here. What you'll want is a ratchet with a 3/8 drive end on it ... is a square hole in our tensioner here- Here's a shot of it from the other angle of my ratchet in my tensioner... going to take your ratchet and you're going to want to push it clockwise. As I push down on the tensioner, that loosens the belt, I can remove it up here from the alternator and slowly let my wrench back being careful not to pinch my hand in anything.

Now my belt will come off. Check the condition of your belt. Ours is in pretty good shape, see there's a little bit of cracking on the ribs but that's not too big of a deal. You want to check the whole length. Where they sometimes can get bad is where they're joined together and if it's getting bad there you'll know it because you'll see it and I don't see it so this one's okay. If you do need a new belt, we carry them at Can't really film putting this on too well but I'll try and put it together and detail as best I can. I'm putting a loop down and around the crank pulley which is the largest pulley at the bottom of the engine. Loop it down there. Then I'll bring it back up and over my water pump right here on top. Then way down and around my AC pulley which is a smaller pulley at the bottom of the engine. Then up and around my idler pulley here and on this side around my tensioner pulley. Then around my power steering pulley.

Now basically I have the whole thing routed except for having it on the alternator. Okay. Here's my belt. I took a piece of pipe actually, you can see it at the top of the camera there, put it onto my ratchet that's in my tensioner and that gives me a lot more leverage. Pull my tensioner over, put the belt onto my alternator there, let the tension back, take out the pipe, take out the wrench, make sure everything is routed correctly. It appears to be and we're all set.

We hope this helps you out. Brought to you by, your source for quality replacement parts and the best service on the internet. Please feel free to call us toll free 888-844-3393. We're the company that's here for you on the internet and in person.

Tools needed for replacement:

    Ratchets & Related

  • 3/8 Inch Drive Ratchet

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