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How To Replace Fog Lights 03-06 GMC Sierra 2500

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How To Replace Fog Lights 03-06 GMC Sierra 2500

Created on: 2021-01-16

Check out this helpful 1A video on how to replace the fog light on your 03-06 GMC Sierra 2500.

  1. step 1 :Removing the Fog Light
    • Remove the two 10mm bolts from the fog light bracket
    • Pry the fog light to the side with a flat blade screwdriver
    • Pull the fog light out of the bracket
    • Mark the position of the fog light adjusting screw
    • Remove the adjusting screw with a 5/32 inch Allen wrench
    • Pull the fog light bulb and socket out of the light
    • Turn the light sideways and pull it out through the front of the bumper
    • Pull the bracket out from under the bumper
    • Unplug the fog light bulb
  2. step 2 :Installing the New Fog Light
    • Pinch the plastic adjusting screw clip and pull it out of the bracket
    • Hang the bracket in place
    • Turn the fog light sideways and push it in through the front bumper
    • Start the adjusting screw
    • Tighten the adjusting screw with the 5/32 Allen Wrench
    • Push the plastic adjusting screw clip into the bracket
    • Turn the adjusting screw to the marked position
    • Insert the two 10mm bolts into the fog light bracket
    • Push the bulb into the fog light
    • Connect the wiring harness to the light bulb
    • Test and aim the fog lights

Tools needed for replacement

  • Hex Wrenches

    5/32 Inch Allen Wrench

  • Ratchets & Related


  • Screwdrivers & Related

    Flat Blade Screwdriver

  • Sockets - Metric

    10mm Socket

Installation Video
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Hi, I'm Mike Green. I'm one of the owners of 1A Auto. I want to help you save time and money repairing or 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'll be replacing a fog light on a 2004 GMC Sierra. These fit the 2003 to 2006 Sierra. This is a fairly easy project. It only requires a 10 millimeter socket and wrench and a 5/32 inch Allen wrench.

We're going to be switching back and forth from underneath and above. Here is your back of your fog light and you can see up in there, that's one of the bolts that holds it in. There's 2 bolts that bolt in from the top. Now don't get too excited here. It's not just 2 bolts. Pull it out, unplug it, plug it back in. It's actually more complicated than that. You're actually going to have to take apart the light from the bracket to be able to get it out of the truck. It's a little bit close quarters.

We're going to start by removing the 2 bolts. They're 10 millimeter bolts and there's room to get up in there. You'll see my big paws, I can get my hand and wrench up in there and remove those bolts. You basically just have to go right up in behind the bumper and you'll see me reach over further and I can get a hold of the other one. They're not too bad to get a hold of. Obviously I have it up on the lift which is nice but it's still, even laying on your driveway or whatever, you can get up in there.

Once you have that done, I'm going to show you the light off of the car here. What I want to show you is how to remove the light from the actual bracket. Basically you just use a screwdriver, a regular screwdriver and just kind of pry to the side. That comes out of there. Don't pry too hard. Then, on the other side it's just 2 pins and they come right apart. Now, going to go back on the car here. Just flip that back together real quick. We'll need to do that process later.

Back on the car here, now you've got to unbolt it so you can move it around a little bit, reach in there with your screwdriver and separate out that side. It takes a little bit of finagling when you're working in close quarters like that but eventually it'll pop out. From the other side, you can take it out. Now, your light is still connected to the bracket by the adjusting screw. If you have a broken light, yje adjusting screw is a 5/32 inch Allen screw. If your light's broken, what you can do is just mark the adjusting screw up near here it goes into the light and this gives you a reference point of where your light was aimed before. I can talk more about that later. Now, I'm just taking the light out of the back. We'll go back to the front view here and you just kind of turn the light to the side and it pulls out of the front and then the bracket comes right out nicely.

With it altogether, you can't do it like that but it's not too much of a pain to get it apart. Now, I'm just going to unplug the bulb so it doesn't end up getting damaged. What you want to do if you've got a new light is take it apart and you want to take the adjusting screw out and you just kind of pinch that clip and it pulls out of the bracket just like that.

To put it back together, you put your bracker up in there. You don't need to bolt it in at this point, just kind of put it up in there and hang it up in there. Take your light and if you got confused or whatever, you want to know, you're not sure which side it up, there's writing on the lense, that writing should obviously be right side up and then there's a little rectangular hole right below the light hole and that should be on the bottom. Now, you just kind of place the light in there and just get it into position. You don't have to worry about it too much and just kind of finagle it in there. There it is. Now, we'll go back underneath and your adjusting screw that you have, you just put it up in there and you can start it with your hand. This is just really the easiest way to do it and make sure you get that adjusting screw in there straight. You don't want to try and put in there crooked and strip that little plastic nut that it goes into and then you just start it in there and pretty soon that clip will work its way into the square hole. Obviously you want to make sure that it clips in the right way. The teeth have to be the certain way, they have to be into the narrow way so that it will clip. Once you get a certain distance, than you can just kind of push the clip up in. You can't do it too early because you'll bottom out the light on the bracket and you don't want that to happen. I just put my thumb up in there, push it in. It's all set. Just do the allen screw back to basically the same position as you had it before. Like I said, when you take it apart, you can before you take it apart, you can mark it up near that little round plastic nut there. Mark where it is and you can either use your original adjusting screw or you can mark the new adjusting screw and get it basically into the same position.

Now we're going to just rebolt it back in. Again, you can get your hands up in there pretty easy. Just want to make sure that you really push the bolts back down into the clips and make sure you get it right. You can see here I actually have a little problem with the second one. What I have to do is kind of reach up in there with a screw driver and just slide the clip back into the place. Like I said, just make sure, when you put those in, you push them down into place, get them going a few turns and then pull back out and make sure you got a good bite into the clips. Once they're up in there, tighten them up and then I'm just replacing the bulb and then hook up the harness and you're pretty much good. You might want to turn them on. Obviously make sure everything's working right. Aim them, make sure that they're not pointing up at the sky or anything like that but be on that and you're pretty much all set.

We hope this video 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:

    Hex Wrenches

  • 5/32 Inch Allen Wrench

  • Ratchets & Related

  • Ratchet

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - Metric

  • 10mm Socket

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