What to do if the wheel bearing breaks

[mconforti]

Over the weekend, I heard strange noises coming from the rear of my car. I took it to my local garage and they told me that I had to get the wheel bearing replaced on one of the rear wheels (it was wobbling all over the place).

If the bearing had broekn whilst I was driving, the wheel could have locked up. In this case, what would have been the best way to stop the car safely?

[michael769]

Over the weekend, I heard strange noises coming from the rear of my car. I took it to my local garage and they told me that I had to get the wheel bearing replaced on one of the rear wheels (it was wobbling all over the place).

If the bearing had broekn whilst I was driving, the wheel could have locked up. In this case, what would have been the best way to stop the car safely?

If a single wheel siezed completly on the car you would lose virually all steering control and the vehicle would lurch in the direction of the frozen wheel, whith the steering wheel most likely having been wrenched from your grasp. Meanwhile if it was a driving wheel, something would have to give in the drive train, most likely the CV joint or part of the differential would tear itself apart. The ABS system would have gone into an error condition and shut off as would any ESP or traction control systems. While you would still have full braking, steering would be very difficult. All you can do is grasp the streering wheel hard and try to steer away from the lurch while braking firmly to bring the car to a halt.

Of course the wheel bearings do not fail without warning, and you would get considerable warning, first with noise and then increasing vibration, the only safe strategy is to stop and investigate at that point. If you do choose to drive on drive very slowly.

FWIW I would not agree that the bearing would have siezed, in my experience the wheel movement would tear the bearing apart leading to ever increasing vibration and noise and making the car progressivly harder to drive, in a front wheel (on FW drive cars) the CV jouint would eventually seperare causing a loss of power to the drivign wheels and foring the car to a halt. I had a quick look at our "enevitable accident" file and we have never encountered any collissions involving a wheel bearing failure in the last 25 years!

[Renny]

In my experience, if a bearing does seize, it tends to turn either the outer or inner track. This can severly damage the hub or stub axle and will effectively be like a heavy application of the brake to one wheel.

[mph999]

Over the weekend, I heard strange noises coming from the rear of my car. I took it to my local garage and they told me that I had to get the wheel bearing replaced on one of the rear wheels (it was wobbling all over the place).

If the bearing had broekn whilst I was driving, the wheel could have locked up. In this case, what would have been the best way to stop the car safely?

You're at the mercy of fate/luck ...

I had a tyre partly let go on Sun, front right on a bend at about 60mph ... Lets just say it was a bl**dy good job it was

a: A left hand bend
b: Nothing oncoming

as it took me half of the other side of the road to get the car back - and I suspect most of that was luck.

A wheel locking may put the car in a spin - best course of action, stand on brakes and try to lock the wheels, if there is no chance of recovery.

Martin

[TripleS]

Over the weekend, I heard strange noises coming from the rear of my car. I took it to my local garage and they told me that I had to get the wheel bearing replaced on one of the rear wheels (it was wobbling all over the place).

If the bearing had broekn whilst I was driving, the wheel could have locked up. In this case, what would have been the best way to stop the car safely?

You're at the mercy of fate/luck ...

I had a tyre partly let go on Sun, front right on a bend at about 60mph ... Lets just say it was a bl**dy good job it was

a: A left hand bend
b: Nothing oncoming

as it took me half of the other side of the road to get the car back - and I suspect most of that was luck.

A wheel locking may put the car in a spin - best course of action, stand on brakes and try to lock the wheels, if there is no chance of recovery.

Martin

Ooooh, nasty! Two thoughts though:

If it was right front tyre, why is it best that it happened at a LH bend?

Presumably an ABS equipped car would prevent one from locking the wheels, so that option would not be available to help keep things straight(ish) would it?

Best wishes all,
Dave.

[ScoobyChris]

Ooooh, nasty! Two thoughts though:

If it was right front tyre, why is it best that it happened at a LH bend?

Presumably an ABS equipped car would prevent one from locking the wheels, so that option would not be available to help keep things straight(ish) would it?

A couple of thoughts in reply.

On a LH bend there is road to your right and verge/wall/tree/house/hedge to your left. If the car loses half the ability to turn to the left it'll tend to the straight ahead which in this case will be on-road rather than off-road. In the case of a RH bend, it'll be heading for the scenery. As was said though, if there was traffic coming this would have been far less desirable!

My guess on the second one is that the ABS would have logged a fault code if one of the wheels is permanently locked (because of the bearing failing) and disabled itself so it should be possible to even up the braking to all wheels and try and get the car straightish. I suspect it depends on how the ABS handles faults though which you probably won't find out until you're in the situation where you need to know...

Chris

[TripleS]

Ooooh, nasty! Two thoughts though:

If it was right front tyre, why is it best that it happened at a LH bend?

Presumably an ABS equipped car would prevent one from locking the wheels, so that option would not be available to help keep things straight(ish) would it?

A couple of thoughts in reply.

On a LH bend there is road to your right and verge/wall/tree/house/hedge to your left. If the car loses half the ability to turn to the left it'll tend to the straight ahead which in this case will be on-road rather than off-road. In the case of a RH bend, it'll be heading for the scenery. As was said though, if there was traffic coming this would have been far less desirable!

My guess on the second one is that the ABS would have logged a fault code if one of the wheels is permanently locked (because of the bearing failing) and disabled itself so it should be possible to even up the braking to all wheels and try and get the car straightish. I suspect it depends on how the ABS handles faults though which you probably won't find out until you're in the situation where you need to know...

Chris

Hello Chris,

I think if I were to suffer a tyre problem at a bend, I would rather have a chance of hitting something (which in many cases could be soft) on the nearside, rather than run the risk of hitting something hard, and maybe travelling fast, coming the other way.

With regard to ABS systems and how they respond to fault conditions, I can't imagine them detecting a tyre failure and disabling themselves so that one would be allowed to lock the wheels, but my Stressed friend will probably know more about these things.

Best wishes all,
Dave.

[jont]

A couple of thoughts in reply.

On a LH bend there is road to your right and verge/wall/tree/house/hedge to your left. If the car loses half the ability to turn to the left it'll tend to the straight ahead which in this case will be on-road rather than off-road. In the case of a RH bend, it'll be heading for the scenery. As was said though, if there was traffic coming this would have been far less desirable!

OTOH if it's the inside (wrt the direction of the bend) wheel that punctures, it won't be under so much load anyway, so if the front right went on a RH bend you may find that you still get round the bend. The stressed one can probably comment better.

Anyone know how well run-flat tyres work in those sort of situations?

[mph999]

Presumably an ABS equipped car would prevent one from locking the wheels, so that option would not be available to help keep things straight(ish) would it?

Best wishes all,
Dave.

If you're spinning, at somepoint the wheels will stop rotating as the are going sideways, if your foot is hard on the brake, they will not start to rotate again, and so will stay locked ...

Martin

[mph999]

I think if I were to suffer a tyre problem at a bend, I would rather have a chance of hitting something (which in many cases could be soft) on the nearside, rather than run the risk of hitting something hard, and maybe travelling fast, coming the other way.


Best wishes all,
Dave.

If I had gone left, I probably wouldn't be here now ...

Nothing was oncoming, so going right was a better option ...

Martin

[mph999]

Anyone know how well run-flat tyres work in those sort of situations?

It was a run flat, hence the "partly let go" ...

It had been replaced that morning, but the tyre place didn't inflate it, I'd reset the run flat warning and so the car thought it was inflated, and unfortunately, so did I. Car felt fine, "tramlined" a bit more than normal, but I'd put that down to the road surface.

Eventually, see as I'd been driving it over the 50mph you should when flat, it decided it didn't want to play anymore ...

Upto 50, and driven "gently" it was fine, and would have done many more miles than it did, but oon twisty roads, they took their toll and shortened what it could do.

Anyway, put some air in it, and it felt absolutly fine, though I went straight back to the tyre place and "had a word". They replaced it and although it was severly weakened, it was still complete and tyre shaped.

One for experience ...

Martin

[TripleS]

Presumably an ABS equipped car would prevent one from locking the wheels, so that option would not be available to help keep things straight(ish) would it?

Best wishes all,
Dave.

If you're spinning, at some point the wheels will stop rotating as they are going sideways, if your foot is hard on the brake, they will not start to rotate again, and so will stay locked ...

Martin

Yes, I suppose so - if you are spinning, and get to the stage of travelling sideways - but if your motion is mainly forwards I expect the ABS would intervene and limit your choices.

Best wishes all,
Dave.

[ScoobyChris]

With regard to ABS systems and how they respond to fault conditions, I can't imagine them detecting a tyre failure and disabling themselves so that one would be allowed to lock the wheels, but my Stressed friend will probably know more about these things.

Did some Googling and turned up the following site:

http://www.aa1car.com/library/2003/bf50360.htm

On vehicles equipped with anti-lock brakes and hub assemblies with an integral ABS sensor or tone ring, the ABS warning light will come on if a wheel-speed sensor is reading erratically or the signal is lost. The ABS system will set a fault code that corresponds to the sensor location (left front, right front, right rear or left rear) and disable the ABS system until the fault is fixed. On these vehicles, the only way to get the ABS light to go out is to replace the hub assembly (assuming the problem isn't a simple wiring fault or loose connector).

Of course, I have no way of verifying that, but I do know that if a single ABS sensor fails (or is left unplugged after a brake change ), the system will throw up the dash warning light and disable the entire system. I guess the thinking is that as it can't ascertain the state of the system, it is safer to disable the ABS completely than leave it available in an unpredictable state?

Chris

[TripleS]

With regard to ABS systems and how they respond to fault conditions, I can't imagine them detecting a tyre failure and disabling themselves so that one would be allowed to lock the wheels, but my Stressed friend will probably know more about these things.

Did some Googling and turned up the following site:

http://www.aa1car.com/library/2003/bf50360.htm

On vehicles equipped with anti-lock brakes and hub assemblies with an integral ABS sensor or tone ring, the ABS warning light will come on if a wheel-speed sensor is reading erratically or the signal is lost. The ABS system will set a fault code that corresponds to the sensor location (left front, right front, right rear or left rear) and disable the ABS system until the fault is fixed. On these vehicles, the only way to get the ABS light to go out is to replace the hub assembly (assuming the problem isn't a simple wiring fault or loose connector).

Of course, I have no way of verifying that, but I do know that if a single ABS sensor fails (or is left unplugged after a brake change ), the system will throw up the dash warning light and disable the entire system. I guess the thinking is that as it can't ascertain the state of the system, it is safer to disable the ABS completely than leave it available in an unpredictable state?

Chris

I have virtually no understanding of how these things work, so thanks for that, Chris.

The only times I've caused the ABS to activate on our 406 have been when I've put a wheel over the edge onto some muddy stuff when meeting another vehicle on a narrow country road, and once when braking from about 15 mph on a snowy surface.

In the latter case I felt that the car responded less well to the braking than it would have done without ABS, but it was only my feeling and not based on any proper comparison.

At the risk of ruffling a few feathers I must say that ABS and ESP etc. are not strong selling points in my choice of a car (sorry Mark from W in H) but it's becoming a bit academic now as most cars presumably are equipped with these systems as standard.

Best wishes all,
Dave - still stuck in the dark ages.

[Renny]

The only times I've caused the ABS to activate on our 406 have been when I've put a wheel over the edge onto some muddy stuff when meeting another vehicle on a narrow country road, and once when braking from about 15 mph on a snowy surface.

In the latter case I felt that the car responded less well to the braking than it would have done without ABS, but it was only my feeling and not based on any proper comparison.

In snow, it is well recognised that ABS will lengthen the stopping distance. A locked wheel forms a wedge build-up of snow in front of it that reduces the stopping distance.