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Wheel Bearings on Cars and Trucks Sealed Bearing vs Adjustable Bearing

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Created on: 2020-10-29

Do you know the difference between sealed wheel bearings, and adjustable wheel bearings on cars and trucks?

Hey, friends. It's Len here from 1A Auto. In this video, we're going to go over some of the differences you might find between sealed bearings, or even adjustable wheel bearings. Let's get started.

Okay, friends. So first, let's start talking about sealed wheel bearings. That's something that looks a lot like this. It has the hub in the front, which has your lug studs there, and then it has the bearing in the rear. And, of course, they're completely pressed together, and they're non-serviceable. Essentially, if you have movement that looks anything like what's going on here, this bearing would be no good, and there's no further diagnosis.

A sealed bearing like this is something that's going to be more commonly found on maybe a four-wheel-drive truck of some sort, or even a passenger vehicle, such as a car. For diagnosing issues with a sealed bearing like this, it's pretty cut and dry. Essentially, you want to check for movement, either up and down, 12 and 6, or even side to side, 3 and 9. Other than that, what you might happen to notice is when you're driving down the road, you might hear a faint humming noise, especially when you turn from one side or to the other. If you're turning right and you hear humming noise, and then you straighten out, the humming noise goes away, that's telling you that your left side bearing's no good and vice versa. Other than that, something that you might find, if you have ABS, there's an ABS light on your dash. But for our particular vehicle, we have a two-wheel-drive truck in the shop. So that's telling me that we're going to have adjustable bearings back here. I want to let you take a little look at what's going on because I think it's kind of interesting.

So now that we have the wheel off, we have a view of where the bearings are going to be. They're going to be right inside of this area of the rotor located right behind this cap. If I was to take this off, just like that, you can see where the adjustment point is. This is something that's great to adjust every once in a while as like a serviceable item. But if you have a lot of movement, what we have on this vehicle, it's something that you're going to have to actually physically completely take apart and inspect the bearings thoroughly. With that said, to get this apart, what I would, of course, have to do would be take off this cover like I did. We're going to remove the caliper and hang it safely, so there's nothing putting pressure on this flex hose. And then we'll start taking this apart so I can show you what's going on.

Now, that we have the lock out of the way, we have a clear view of the nut right here. This is the adjustment nut that actually makes it so you'll either have movement from the bearings, or you won't have any movement from the bearings. If you have movement that looks like ours, which you can see quite a bit, that means that this is de-adjusted too far. And if I can turn it with my fingers like I can right here, that's a definite cause of why it's loose.
So now, I'll just wiggle this around. We're going to have our washer, don't lose that. And this is your outer bearing right here. A lot of times, you can just kind of move it around with your fingers. And you can see these areas right there, those are the roller bearings. If you can see that they move around quite a bit in there, well, then that's telling you that they're very worn. If they move a little bit, that's very normal, and it's actually supposed to do that, but this is excessive. Now, at this point, you would just go ahead and remove your rotor. And then you can see from the backside where your bearing's going to be located, but there's actually a seal that's right there that's kind of holding it in there and keeping the moisture out.

To get the seal out of here to be able to inspect the bearings, the easiest way to do that would be to take your nut. We're going to put it right back here on the stud, just a few good threads. Slide the rotor back over it. And then I'm going to drag the rotor down and pull out at the same time and it should separate the two. So there's our bearing right there. And just by touching it, I can feel that this is moving around quite a bit. We'll clean it down so you can have a better look.

Okay, so we brought our parts over to the bench here so we can have a nice, clear look at them. We've got our rotor that we remove the bearings from. We have the large one that was on the backside there. And, of course, that was hidden behind this seal, which we removed. And then, of course, we have the forward bearing as well. What I always like to do is inspect all the little roller bearings here. And, in all honesty, this one's in really poor condition. I've done a lot of these bearings, and I've never really seen any that are this bad. If you have any chips or chunks that are taken out of any of your roller bearings, that's obviously going to be a major issue. This one right here is in very poor condition. The more I turn it, the more I can see all the areas where this pick is getting caught on. And obviously, this is going to cause a noise and potentially fail over time. Look at that.

Another way to check your bearings once they're clean is to just kind of shake them like this. And that's kind of moving the race around against the cage, and you can see a large gap where those bearings are pretty much ready to separate out of there. There should not be this much movement in there. That's telling me that there's a lot of wear to this bearing, and it's in very poor condition once again.

Now, let's have a look at our inner bearing here. That's the larger of the two, like I said. When you look at these bearings, you've got the little rollers here, you want to look for scouring lines, lines that look like this. That's not really super bad. But if you've got some more scouring in there where there's a whole bunch of lines, well, that kind of tells you that there's probably debris, or even not enough lubricity inside the grease that you have inside there. Of course, that would become an issue, and you'd see something like this. Other than that, something else that you might see on bearings that's pretty common is if they overheat. If your bearings look like this, or even if they just kind of look as though they're starting to get blued or discolored in any areas, that overall means that they've been overheating at some point. Usually, why that would happen is because your grease has broken down, and it's lost its lubricity. So not just talking about that. But now, of course, if we were to hang this like what we did with a smaller bearing, you can see that there's quite a bit of movement there. It's pretty common to have some movement like that. This is, I would say, mildly excessive. It might be something that I would want to replace the bearing for, but it has all sorts of other conditions as well that would kind of tell me that I should replace it anyways.

Okay, so let's just kind of narrow this down for you a little bit. If you have bearings that look just like ours, whether they've got the marks that show that they were cooked in some way or overheated, I should say, or even if they look like they were scoured, they have a whole bunch of slash lines going across them, or maybe even chunks coming out of it like what we have here, obviously, that's going to be an issue. Also, if you take the cage and you move it around with the bearing itself, and you can see those roller bearings are just kind of flopping around and there's a lot of movement, it's definitely something that you're going to want to replace. These bearings aren't something that you would replace one at a time. If you're replacing the outer one, you do the inner. If you're doing the inner, you do the outer. And, in all honesty, for me, personally, I would replace the other side at the same time only because, well, it's a wear item, and why not. With that said, if you're replacing the bearings, or even if you're servicing the bearings, anytime you remove a seal, you need to go ahead and replace it as well. Obviously, if you have brakes that look like ours do on this particular vehicle, that's going to be something that you would want to replace as well because you can tell by the condition of this rotor that it's really not in great condition. And in all honesty, it could have caused part of the problem with the bearings because with these cooling fins being like this, there's no way that this rotor can cool itself down the way that it needs to.

Okay, so you saw what the other side of the vehicle look like. Now, what we're going to do on this side right here is we're just going to get the wheel off, and we're going to kind of inspect what's going on back there.
Now, with the caliper off, we're going to remove this cover right here. Perfect. So now let's go with the assumption that you just removed the cover, and you can see that it has beautiful, clean new grease inside there. I'm going to show you how to give it a quick adjustment to get you down the road. Let's get our safety clip off of here, little cotter pin. Get that right out of the way. This right here is a lock. It's very important. You need to make sure that you keep it and you reuse it.

At this point, I'm just going to wipe this down so I can grab on to the nut. Looks like I've got some movement here. If you can move this with your fingers, then you know it's entirely too loose.

To adjust this, there's a couple things that you need to think about, whether or not the grease has been in here for a little while but like I said, it's still in good condition, or you just service the bearings or replace them and you just repacked them. If you've repacked the bearings, what you're going to need to do is go ahead and grab onto this nut and you're going to kind of work it, tighten, loosen, tighten, loosen until it's basically bottomed out. While you're doing this, give the rotor a little spin like that. And what you're probably going to notice is every time you do it, the nut's going to go just a little bit further, little bit further, little bit further. The reason for that is because it's going to be pushing out all the air that's in between the two bearings right there, and it's going to come out between this area right here where the front bearing is. But if you're just adjusting your existing bearings just kind of quick on the fly because you noticed that they were a little loose, what you would do is just take your pliers like what I'm doing here, and basically just kind of turn it like that. I like to go back and forth, that's going to help push out any air that might be in there, which is less likely than if you just replace the bearings and, of course, still give it that spin. And just keep doing this. You only want to go until it bottoms out. You don't want to go any past that. So once it bottoms, don't grip it and try to target because we're not trying to put any force on this. Essentially, we just want to make sure that the bearings are inside the rotor, and make sure that the rotor has no movement. This feels great. So let's continue.

Let's go ahead and put our little lock on here. When you set it, you want to make sure that the grooves line up with the hole on your actual axle stub there, put your cotter pin through, and then make sure you lock it down.

All right, so now that we have this nice and adjusted as close as we think it can be, go ahead and give it a little shake. See if you feel any movement. I don't feel any like that, so that feels great. The next thing you're going to want to do is grab your cover. The next thing we're going to want to do is take a look at our cover. This edge right here is the area that's going to press inside the rotor. You need to make sure it's nice and clean right there on the cover and, of course, on the rotor itself on the inner portion.

Now, let's grab our cap, clean up this area right along the outside there and the area where that's going to ride on the rotor itself, put a little bit of RTV around the actual cap itself, which is a gasket maker. Go ahead and put it on here, give it a couple loving bongs, and seal it up tight.

Okay, so now we have the wheel back on there. Let's go ahead and test what we've done. Give it a little wiggle up and down. Oh, yeah, that's tight. Side to side, that feels amazing. And, of course, give it a nice little spin. Make sure it spins freely without any restriction.

Okay, so as you can see, adjustable bearings are definitely a lot more maintenance for the consumer than a nice sealed bearing like this. With the adjustable bearings, you want to make sure that they're continuously greased, they're nice and clean, and, of course, they're adjusted properly. If you have a bearing like this, a nice sealed bearing, if you have any movement, well, just unbolt it from the backside, throw it in the recycling bin, and go ahead and replace it. Easy peasy.

Okay, friends, we tried to make a nice informational video for you about the differences between adjustable bearings or sealed bearings. Hopefully, you learned a little something along the way. If you did and you want to talk about it, leave it in the comment section below because I always love to hear from you. While you're at it, if you like the video, feel free to smash on that Like button for me. It would mean the world. While you're at it, why don't you go ahead and subscribe and ring the bell, that way there you can be kept up with all of our latest content. Thanks.

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