How to Replace Alternator 2003-04 Chevy Silverado

Okay, friends, one of the first things we need to do is remove our negative battery terminal from the battery. Go ahead and use your 8-millimeter and get it right off of there. Set that away so there's no way it can contact the terminal on the battery. If you were to look right down here, you're gonna see a clamp. If you were to look at the other end where it connects onto the throttle body, you're gonna see another clamp. You'd go ahead and loosen those up. Also, if you come right up here, you're gonna see an 8-millimeter bolt. If you loosen that up, you can take this right out. Once you have that out of the way, and the clamps are loosened, you can wiggle this around. I'm gonna draw it off of the throttle body right here and I'm gonna come right there, take it off of right here, remove it from the vehicle.

So, now that we have the intake and the little shell out of the way here, it gives us a nice, clear view. You don't necessarily need to take off the shell, but I just like to have it out of the way. Go ahead and relieve your tension like that. And then I'm just gonna take the belt off of the idler pulley here and then I can let go of that. We'll get our serpentine belt tool right out of the way. Let's go ahead and remove the belt. All right. Now that we've got the belts out of the way, let's go ahead and grab onto this little rubber boot on the backside of the alternator here, and it's gonna expose a 10-millimeter nut. Remove that nut and pull this wire aside. Carefully set this aside. Now we're gonna get this clip off of here. It's gonna have a little flippy-do that you're gonna grab with your finger, pull it away, and lift it up. There it is right there. I pulled on it and then I lifted this right out. Now, we're gonna remove our two mounting bolts that hold the alternator to the bracket. Next, we're gonna use a nice long pry bar. I'm gonna come in between the bracket and the alternator, see if I can pry it up and out of here.

There it is, friends. We're gonna spray down these two areas right here with some penetrant spray. To install the new alternator, these are gonna have to be moved. Get a nice little hammer and bonk on these from the backside towards the front. Carefully take your alternator, rest it down inside this area. You should notice it falls right in nice and easy. The reason for that is because we push these ears towards the front of the vehicle. If you didn't, you're gonna have an issue getting the alternator in. Take your two bolts, start on both in before you tighten either of them down.

You'll notice as you start tightening this down, that piece that you bonked from the back towards the front is gonna start moving to press up against the alternator. There we are. Okay. Once they're bottomed out, just go ahead and give it a teeny bit more. Now, if you were to grab onto that wire, you removed off the backside of that alternator, you're gonna notice it needs to be cleaned up more than likely. You definitely don't wanna have it full of gunk and debris in a way that it's gonna cause some sort of issue where you won't be able to charge your battery from your alternator. Carefully clean it up.

Take the new nut off the back of your alternator. Put your nice clean end on the alternator and then go ahead and put on the nut. Make sure you tighten it down. Okay. The stud that comes out of the alternator, as you can tell is a very small stud. So, you don't necessarily need to have a lot of pressure holding the nut that holds the wire, okay? You don't wanna break off that stud cause then you need to get yourself a new alternator. Go ahead and put that boot back on there. That's super important because you don't want anything to ground out against there. Next, we're gonna grab the wiring for this. There it is. Click it right in. Give it a nice tug. Make sure it's completely secured. Go ahead and take one side, go down and around the passenger side of the water pump, which is this right here, and then put it over the crank, which is the main pulley over there. I'm just gonna circle it, put it up, then slide it around.

I'm gonna take one and I'm gonna come up and over the tensioner right here and then the other side, I'm gonna bring it down and around the water pump and then underneath the power steering pump, it's gonna fit right inside the ribs perfectly. And we're gonna come up, make sure it's sitting in those ribs. There it is. Come up and over the alternator right here, this looks good. Make sure everything's situated approximately where it needs to be. That looks great. I'm gonna grab my tensioner tool. Get on there. Relieve tension. Now we'll take this, bring it right underneath the idler pulley. This is your idler pulley. Get our tool off. Give it a nice tug and then, of course, double-check all of your pulleys. Every one of them has the rib side that goes up against the belt, you need to make sure it's sitting perfectly inside the ribs.

If you're wondering what your belt routing should look like, you can find it right on the front. Get our air intake back on here. I'm just gonna go right underneath this hose here. Line it up there. Grab this. Slide it in, push it all the way in so it's up against the whole throttle body. Make sure your clamps are nice and tight. Your hose over here should have a little clippy-do. Ours is actually broken, but it's gonna push in right there and that'll hold it secure. Put this cover back on here, just slide it all the way back so it's sitting inside the pitons. Put this down and tighten up your bolt. It's time to reconnect the battery. Make sure it's secure and this cannot move around.