How to Replace Serpentine Belt Tensioner 2004-08 Ford F-150

Okay friends. To get started on replacing our serpentine belt tensioner, we're gonna have to remove our serpentine belt. It's always a great idea to inspect the serpentine belt to make sure it's in good condition. Ours is not in good condition so I'm gonna be replacing it. If you're worried about the belt routing, you can either draw what this looks like on a piece of paper or of course, if you were to look at the front of your vehicle right along the cowl, you should see a nice diagram here for you and just go by that. With that said, we're gonna use the serpentine belt tool and we're gonna come right down along this area to the serpentine belt tensioner right in the center. We're gonna turn this counterclockwise and it'll relieve tension of the belt and then we'll get the belt out of the way. Counterclockwise and we'll get the belt right off. Release that. Get our tool out of the way. Remove the belt fully so you can inspect it. I'll set that aside for now. Now looking at the serpentine belt tensioner, you're gonna be able to see the mounting bolt located right here. To get to that, you're gonna use a T-50 Torx socket. That socket's gonna look like this and it looks like a star. You need a T-50. Put this right on there. We're gonna turn it counterclockwise obviously and remove the center bolt.

There we are. All right. Now that we've got that like that, we should be able to break this smooth from the engine and remove it. I'll just remove the bolt from our old tensioner. We can go ahead and install it into our new tensioner. Just give them a quick look over. Make sure they're the same. This looks perfect as I would expect. Let's get ready for an install. Looking at the back of the tensioner, you're gonna see there's two little pitons. If you look down at the engine where it's supposed to mount, you're gonna see a hole and another hole. We need, obviously, those pitons to line up with there, and the bolt to line up with its bolt hole. Press down here. Line up those pitons and of course, our bolt. We'll start this bolt in and then we're gonna snug it up. Once we have it bottomed out, we'll torque it to 41 foot-pounds. Okay. That's bottomed out. Let's switch to the torque wrench. Once again, we're torquing this to 41 foot-pounds. That's torqued. Now we wanna compare our old belt to our new belt. I'm just gonna take one finger like this and put it through. Then I'm gonna go down to the other end, same thing, with one finger, put it through. And then I wanna try to line these up. We want them to be approximately the same length overall. This looks great. The next thing that you would wanna do is, of course, turn them to the inside and you'd wanna count those ribs.

For me, personally on mine, I know that my belt was damaged and it was missing a whole rib so I'm just gonna have to go with the imagination that it's there. Count them up. It should come out even. Perfect. Now that we've got the belt up inside the engine compartment area, we just wanna take a quick look at that belt routing. If you have it written down someplace or if you look at that diagram, you're gonna be ready to go. Whenever I'm gonna be replacing my serpentine belt or even just removing and reinstalling, I always like to try to clean out any of the areas on the pulleys as I can. So now we're just gonna open up our belt like this and I'm gonna take this hand right here, I'm gonna go down and around that crank. The crank is the main pulley of the engine so that's where I always like to start. I'm gonna go right around it completely. Try to make sure it's set in there if possible. I'm gonna take the...the ribbed end and I'm gonna go out and around this idler pulley right here. So what I did here is I put the belt around all my pulleys, an exception of just the one. And yeah, you could try to go where the tensioner is but that's gonna be the hardest pulley to put it over last because, of course, you're gonna have your tool in the way. What I would do at this point is I would just hold tension where my finger is now.

I would remove the belt carefully from the power steering pump all the way on the other side, put it on the tensioner just like this. And now, of course, I'm holding pressure again and I'm gonna get my belt tensioner on there on my tool, on my belt tensioner, relieve the tension from it and just try to slide it over the pulley now. Be careful for any pinch points. You don't wanna get your finger pinched in any way. Once you feel as though you get your belt on there, it's ultra important to make sure you double check all of your pulleys. What I mean by that is you wanna make sure that the belt is sitting directly inside of all the grooves on the pulley. If you notice that the belt is hanging off on one side or the other, you're gonna cause detrimental damage to your belt and you're gonna have to replace it again. Nobody wants to do that. Double-check all the way around all of your pulleys. You can feel around. This actually feels really great. All right. Let's start it up and double-check it. And when I start this up, I'm only gonna run it for maybe five seconds and then I'm gonna turn it right off and I'm gonna double-check to make sure it's sitting the way that it needs to. After a short amount of time of running, you should very easily be able to see if you missed a tooth on your belt routing. Okay. So now I'm just double-checking. I always like to double, even triple-check my work sometimes. This feels perfect. All right. Next thing, close the hood. Take it for a road test.