Hey, friends. It's Len here from 1A Auto. Today, we've got a vehicle in the shop and
we've got a bad CV axle boot. We wanna show you what can happen with that
and a couple possibilities of how it can happen. With that said, let's get right into it. Well, if you're looking down underneath your
vehicle and you happen to see a whole bunch of grease just spraying all over the place,
more than likely it's because one of your CV boots is torn open. Maybe you were doing some work on your vehicle
and you happen to nick the boot in some way. Ah. Maybe you're heating something up and you
melt it a little bit. Oh geez. Oh man. There's lots of possibilities that could cause
an axle boot to split open like this. Is it dangerous to drive? Well, maybe you could drive around for a little
bit like this, but it's gonna of course make a mess. And then of course it's gonna accumulate dirt,
debris, and even water inside there. And it's gonna cause an issue with the CV
joint. I wanna show you what's going on inside the
CV joint so you can see what I'm talking about, but I did wanna show you the mess that could
potentially occur as this is spinning around. Okay, friends, so 1A was nice enough to give
us an axle so we can tear it apart and show you what's going on on the inside. Let's just do a brief overview of what's going
on on the outside. If you were to look down at this end, this
is the portion that's gonna go inside of your transmission. Sometimes this part isn't necessarily gonna
be as long, you might have an area that just kind of ends right about here and this is
gonna slide into the transmission, or otherwise you might have this shaft that's in the transmission
already and it might just slide into the female portion of the axle. So there are a couple different axles that
you may or may not have. With that said, we're gonna move along. This part's gonna be the closest area to the
transmission. If you were to come right along here, this
is the inner CV joint. And it has to be able to move around freely
because as you turn your wheel, this one right here is gonna want to turn and then of course,
this is gonna sway a little bit. Of course, you're gonna have your intermediate
shaft that's in between the two joints right here. And then if you were to go past the outer
joint, you're going to see this splined area right here. The splined areas where it's gonna go right
inside the wheel bearing. And then of course you'd have your nut that
holds it together. So if you were to look at the clamps on these
boots, you're gonna notice that they're special clamps. If for some reason your clamp was broken or
it came off for any reason and your boot could shift, you'd probably wanna replace the clamp,
right? This is definitely not something that you
want to use on an axle joint. I'm sure you can understand the reason for
that without me having to say, but this area right up along here has a little bit of weight
to it. And as this axle is spinning around whether
you're going 20 miles an hour or 60 miles an hour, or maybe you're a speed racer and
I'm not gonna say how fast you're going, but this is spinning, spinning, spinning, right? And so if you have weight that's just kind
of spinning, it's gonna obviously throw off the balance of the axle and you're gonna feel
a shake more than likely in the steering wheel. So it's also super important to talk about
the boots on these CV joints. If the boots are torn, worn, cracked, or anything
like that where dirt and debris or even moisture can get inside, it's gonna cause major issues. So let's take a look at what's going on inside
these CV joints so we can see how that would cause an effect. Okay, so we took off the axle boots for you
so you could have a more clear view of what's going on inside these axles. You're gonna notice that the outer joint is
much different than the inner joint. The outer joint is more complex. It has six ball joints inside of it or little
ball bearings and the inner ones actually gonna have three bearings inside. And the bearings themselves are much different. Let's go ahead and pull this apart. If you were to look at the bearings that are
on the inner portion, you're gonna see all these little needle bearings. They come right along here, okay. That's the actual bearing. And then this metal part rides right on top
of it. Of course, those bearings need to have grease
inside of them. And that's gonna help with friction and everything
and heat dissipation. So that's great. If you had a torn boot, there's potential
that dirt and debris could be making its way inside here and working its way inside of
these bearings right here, which of course is gonna cause an issue. It's gonna bind these up. And of course, if there's moisture, it's gonna
end up seizing these up over time. Now, if you were to follow the shaft out towards
the output aspect of the axle, you're going to see a much different looking joint. This is actually a CV joint right here. It has six little ball bearings inside of
it and they run inside grooves that go along the outer housing. And then of course, they go along this portion
right here. This center area right there is just the race
and that just kind of holds the ball bearings from moving around. They're supposed to move around like this,
in and out of the grooves, but this protects them from kind of just falling out and going
inside the boot and doing whatever they want. Kind of keeps them controlled. Once again, if the boot that was supposed
to be covering this, let moisture or debris inside, you can imagine what dirt or rocks
or anything else is going to do inside this. You need to have this be a nice smooth machine
surface. Now CV joint axles are super important, especially
for front-wheel drive vehicles. The reason for that is because that's where
the power is gonna be coming out of the transmission, going directly to the axle. And it's gonna have to of course, push those
wheels, which is going to move your vehicle down the road. If your vehicle was just going in a straight
line all the time, you wouldn't necessarily need to have a joint like this. But if you're driving in normal circumstances
where you have to maybe go left or right, or veer or whatever you have to do, you need
that joint to be able to bend. In extreme cases, maybe you're doing a U-turn
or turning inside a parking lot, trying to park, you're gonna have that axle turned quite
a bit. If you had a regular U-joint in this like
maybe something that was in a truck, what you would probably notice is it would start
to bind if it was this turned. With this joint being this way, I can turn
this. It doesn't matter, I can turn, turn, turn,
and it's not going to have any issues. This is gonna be just fine. I can drive all day around and around in a
circle. As long as there's plenty of lubricant in
here, there won't be any issue. If there was a U-joint, you're going to have
issues. So obviously this isn't an axle. This is a steering shaft, but it does have
a U-joint on there. And it gives me a good way of showing you
what's going on. If you have your constant velocity joint,
I can have this turn completely and it'll still turn just like this, no binding, no
resistance at all. If I was to turn this as far as it would wanna
go, which of course would be super far, we'll say about that far, about the same distance
as this, as I try to turn it, it's going to bind and then loosen up and then bind and
then loosen up. Obviously that's gonna cause a major issue. If you're just going in a straight line or
even just turning a little bit, you're really not gonna have as much of an issue. And with U-joints like this, there's minimal
area to contain the grease. So you're probably gonna have binding issues
like this. I don't know if you can hear that. Turns easy this way, not so much this way. So now if you were doing front end work on
your vehicle, maybe you took off that upper ball joint and you happen to pull your knuckle
away, some people might tell you to be super careful because you might separate your axle. Well, what does that mean? Imagine that there's a boot on this right
here, so you can't tell that there's a joint. Now, if I was to pull down on my control arm
on my knuckle, I should say, and pull it away, that's gonna pull this outer portion out and
it's gonna separate like that. Okay? You wouldn't be able to see this because it's
going to be inside that rubber boot. Well, now you need to try to put this back
together. So now with the boot on there, you have to
try to imagine where everything lines up and kind of feel around. And then you're going to have to try to give
it a push, push, push, push, and more than likely, it's gonna have a lot of trouble going
in. That's because of the way that these are right
here. Now, if these are pushed in the inward position,
you're not gonna be able to get this into the outer portion, right? So what you would have to do is just try to
separate all three of them, put them so they're on their outer most aspect and then it should
just slide right in, which of course would be very difficult to do if it was covered
in grease and of course a boot over the top. So it's super important if you know, you're
doing front end work and you're going to be pulling that knuckle away from the car and
you might separate the axle, just go ahead and loosen up that axle nut right down on
this end, push this through a little bit so it's coming through from the wheel bearing,
that's gonna give you a little bit more slack and then that way there, when you're doing
the front end work and you're all done, if you happen to pull the axle out this far,
it's really not that big of a deal. It'll just slide back in. If you happen to pull it out too far, like
I said before, this part is stuck inside the car or truck, whatever you're dealing with
and then you try to put this back in, it's going to be really difficult to do. I mean, you can kind of move it around usually
and you'll probably be able to get it in, but it's going to be very hard. It's much easier just to make sure that you
don't actually separate the axle in the first place. Now, if you happen to notice that you have
a rip boot and you've determined that there isn't very much contamination, you can try
to replace just that boot and of course the corresponding clamps. But for me, time is money. That's gonna take probably a lot of time and
a lot of work. I would just go on down to 1aauto.com and
I would order myself a new one. Okay, friends, we had a lot of fun making
this video. Hopefully you learned a little something along
the way. If you got something to say, leave it in the
comment section below. While you're at it, if you like the video,
why don't you smash on that like button for me? Would mean everything to me. And of course, subscribe and ring the bell
that way there you can be kept up with all of our latest content. Thanks. Mark: Thanks for watching. Visit 1aauto.com for quality auto parts shipped
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