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How to Replace 90 Amp Alternator 98 Dodge Durango

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  1. step : Disconnect the battery (1:00)
    • Use a 12 mm wrench to disconnect the negative battery terminal
  2. step : Remove the alternator (1:11)
    • Remove the serpentine belt by using a 15 mm socket and ratchet to release the tension from the tensioner pulley.
    • Remove the 10 mm bolt and the two 7 mm nuts on the back of the alternator.
    • Remove the two 14 mm bolts at the bottom of the alternator.
    • Disconnect the alternator from the wiring harness.
    • Pull it up and out of the vehicle.
  3. step : Install the new alternator (4:40)
    • Place the alternator down into its mounting.
    • Plug in the wiring harness.
    • Secure with the 14, 10 and 7 mm bolts.
    • Use your serpentine belt routing diagram to put your serpentine belt back on.
    • Use your 15 mm socket and ratchet to release the tension from the tensioner and get the belt over the last pulley.
  4. step : Reconnect the battery (9:53)
    • Use your 12 mm wrench to reconnect the negative battery terminal

Brought to you by, your source for quality auto replacement parts and the bets service on the internet. Hi, I'm Mike Green. I'm one of the owners of 1AAuto. I want to help you save time and money repairing and maintaining your vehicle. I'm going to use my 20 plus years experience restoring and repairing cars and trucks like this to show you the correct way to install parts from The right parts installed correctly, that's going to save you time and money. Thank you and enjoy the video.

In this video, we're going to replace the alternator on this '98 Dodge Durango, same as most Durangoes from '98 to '03 and also even Dakotas. Fairly easy. Tools you'll need, 12 and 14 millimeter wrenches, 7, 10, 14 and 15 millimeter sockets with ratchet and maybe even extension.

Disconnect the negative battery cable. Should be a 12 millimeter wrench. As you can maybe see, this is turning so I'm just going to hold that with a 13 millimeter wrench. Then you need to remove the serpentine belt from the alternator. You can do that by using a 15 millimeter socket. Put your socket and ratchet right down here on your belt tensioner then pull this clockwise. You can see that loosens the tension on the belt. Just flip your belt right off your alternator. Let the tensioner back. Just leave the belt right down there. Now, you have three leads to disconnect from the back of your alternator. I can't really film it but this one here is a 10 millimeter. You need to put your socket and ratchet in from the back, right in the middle of it. Like I said, 10 millimeter socket. That lead comes off. Then right in here, there's two 7 millimeter nuts. I'll go without the extension. You cannot drop those down into the engine. Then here's another 10 millimeter nut that holds this bracket on. All right, the harnesses are all disconnected. You want to remove a bolt here and then another one down here. These are both 14 millimeters.

This one down here has a nut on this end so I'm going to put the 14 millimeter wrench on that end to hold it. I'll remove the nut the rest of the way with my fingers here. I'll remove this 14 millimeter bolt. Pull this bolt all the way out. Just rotate it then just push it out through the back here, pull everything out of the way. There it is out. Here's our original alternator. New alternator from 1A Auto. This original one is fine so I am going to install this back in the vehicle. Just want to show you that when you order one from 1A Auto, you're going to get the right thing. All the mounting points are all the same. Through the plastic, it's got the correct pulley on and everything. The new one from 1A Auto is going to go in there just the same as the original. Like I said, this one is in fine shape. It works fine. I'm just going to reinstall it to show you. Reinstall it, you can see I've got kind of the wishbone, double wishbone over here toward the outside of the vehicle. Just kind of push it down in. Pull these hoses up some. Just put it right in. Bring it up right that and then kind of twist it so it's in place better. Before we get it down in place, make sure you pull your wires up from underneath.

Sometimes you'll get caught. Take it into place. Work it down there like that. Put your long bolt in. Just kind of work it until that bolt goes through. Then take the nut through the back side. Just do it by hand for right now. Okay. Take our other bolt, put it in, hook it up. Get it started. Then we can tighten these up. Tighten it enough but not incredibly tight. It should be very firm though, probably about 20, 25 to 30 foot pounds. Use our wrench to hold the back side. Now on the back side, put your battery cable on. Get the 10 millimeter nut to start. Move it around like this. Put it around and on. 10 millimeter up at the top. Two 7 millimeter nuts behind. Put the 10 millimeter nuts first. To reinstall the belt, if you took your belt off any further than the alternator, just check your belt routing diagram. It's pretty easy. Again, 15 nut, 15 millimeter socket on your tensioner here. What you want to do is I just pull it up. Make sure it's routed pretty much the same. Pull it up like that. Just pull the tensioner. Then put it up around the alternator. Make sure it's down around that pulley. Quick check. Just make sure the belt is on all the pulleys correctly. Now, reconnect your battery and you're all set.

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

Tools needed for replacement:

    Ratchets & Related

  • Ratchet
  • Socket Extensions

  • Sockets - Metric

  • 14mm Socket
  • 15mm Socket
  • 10mm Socket
  • 7mm Socket

  • Wrenches - Metric

  • 14mm Wrench
  • 12mm Wrench

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