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How to Replace Alternator 03-04 GMC Envoy XL

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How to Replace Alternator 03-04 GMC Envoy XL

Created on: 2021-01-16

Check out this video to learn how to replace the alternator in your 02-09 GMC Envoy. 1A Auto will show you how to do it!

  1. step 1 :Disconnecting the Battery
    • Disconnect the negative battery cable with an 8mm wrench
  2. step 2 :Removing the Air Intake Hose
    • Loosen the two air intake hose clamps with a flat blade screwdriver
    • Remove the T30 Torx bolt from the air intake hose
    • Pull the intake hose up and off
  3. step 3 :Removing the Serpentine Belt
    • Familiarize yourself with the belt routing diagram
    • Attach a 15mm socket and ratchet to the tensioner
    • Push the tensioner down to loosen the belt
    • Pull the belt off the center pulley
    • Carefully release the tensioner
    • Pull the belt off the alternator
  4. step 4 :Removing the Alternator
    • Disconnect the alternator wiring harness
    • Pull back the alternator wiring lead boot
    • Remove the 19mm nut from the alternator lead
    • Pull off the alternator lead
    • Remove the two 15mm bolts from the alternator
    • Pry the alternator out with a flat blade screwdriver
  5. step 5 :Installing the New Alternator
    • Hammer out the alternator bolt rings
    • Lower the new alternator into place
    • Insert the two 15mm bolts into the alternator
    • Connect the alternator wiring harness
    • Put the alternator wiring lead on its stud
    • Fasten the 10mm nut onto the wiring lead
    • Put the wiring lead boot into place
  6. step 6 :Reinstalling the Serpentine Belt
    • Pull the belt over the alternator pulley
    • Make sure the belt is routed correctly, using the belt diagram
    • Attach a 15mm socket and ratchet to the tensioner
    • Push the tensioner down to loosen the belt
    • Pull the belt onto the center pulley
    • Carefully release the tensioner
  7. step 7 :Reinstalling the Intake Hose
    • Put the intake hose into place
    • Tighten the two intake hose clamps with a flat blade screwdriver
    • Tighten the T30 bolt into the intake hose
  8. step 8 :Reconnecting the Battery
    • Reconnect the negative battery cable with an 8mm wrench

Tools needed for replacement

  • General Tools

    Hammer

  • Ratchets & Related

    Ratchet

  • Screwdrivers & Related

    Flat Blade Screwdriver

  • Sockets - Metric

    15mm Socket

    8mm Socket

    10mm Socket

  • Star Drivers & Sockets

    T30 Driver

Installation Video
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Brought to you by 1AAuto.com, your source for quality replacement parts and the best service on the Internet.

Hi, I'm Don from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.

In this video, we're going to show you how to replace the alternator on this 2003 GMC Envoy XL with the 5.3 liter V8 engine. The items you'll need for this are a new alternator from 1AAuto.com; 8mm, 10mm, and 15mm socket and ratchet; T30 Torx bit; flat blade screwdriver; and a hammer.

Use an 8mm wrench to disconnect the negative battery cable.

Start off by loosening this hose clamp and this hose clamp, and then, removing this T30 bolt up here, and we'll just fast forward as Mike does that. Now, pull this hose free and then lift that air intake hose up and out.

Next, you want to locate your serpentine belt diagram, which is located right here on the shroud, and you just want to refer to this as you're trying to put the belt back in place and make sure that you have one of these before messing with the belt. Then, using a 15mm socket and ratchet or a 15mm wrench and another wrench for extra leverage, just push down on the tensioner and then pull the belt up and over that center pulley and carefully relieve the tension on the tensioner. Pull the belt off your alternator and then lift up on the tab on this harness and disconnect it.

Pull back this boot and then remove this 10mm nut. Now, remove these two 15mm bolts, and we'll just fast forward as Mike does that. Now, using a large flat blade screwdriver or pry bar, just pull the alternator up and out, and you'll most likely have to pry both sides out.

Using a hammer, just hammer out the rings here, to make it easier to get new the alternator down in place. Make sure the harnesses are out of the way and lower your new alternator down. Line it up and push the 15mm bolts through. We'll fast forward as Mike tightens those up. You do want to make sure that you get that nice and tight. Reconnect the harness. Put this wire back onto the stud and replace that 10mm nut and tighten it up, and slide that boot back up into place.

Put your belt back up over the alternator pulley, and while you're doing that, make sure the belt is on each of the pulleys correctly and that hasn't fallen off any of them. Then, just double check with your belt diagram that the belts in the right order and on each of the pulleys. Put your wrench or socket and ratchet onto the tensioner and pull back on the tensioner, and just push your belt underneath that center pulley. Then, carefully release the tension and make sure your belt is on all the pulleys correctly.

Now, feed your air intake hose back down into place and make sure to push down all the way, and then push this end back into place and then tighten up those two hose clamps, and I'll tighten up the T30 bolt. Then, reconnect your negative battery cable.

We hope this video helps you out. Brought to you by www.1AAuto.com, 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:

    General Tools

  • Hammer

  • Ratchets & Related

  • Ratchet

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - Metric

  • 15mm Socket
  • 8mm Socket
  • 10mm Socket

  • Star Drivers & Sockets

  • T30 Driver

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