Failed front wheel bearings - where did I go wrong?

[ballbag]

To make it like this,
No warmth in your body,
No touch in your kiss....

Sorry.

Two failed front hub assemblies in 15,000km.

Book says to crank axle nut to 490NM.

I used a rigid bar with a 1.5M 3mm stainless pipe snuggly fitted and gave that my best.

Even if that’s not tight enough, I’m struggling to grasp how it allows enough lateral play for the bearing to fail so quickly.

Thoughts?

Next one goes on with the 1300NM Milwaukee.

[goingbush]

Britpart bearings ??

[ballbag]

Negative.

[goingbush]

I would not rattle gun the bearing on & IMO no need to go past 450 , The Iveco 4x4 uses similar unit bearings to the D2 , 650NM rear and 450NM up front, I have a 3/4 drive 450nm torque wrench & do the front & rears up to 450 . Ive had an original rear SKF fail at 70k (probably tightened past 650 because it took a 2m extension to crack it off) , bought a Febest bearing (similar price & reputation to Britpart) & tightened to 450 & no issues so far, 30,000km on. 650 is too much in my book.

[ballbag]

Yeah it’s loads isn’t it.

How long is that torque wrench of yours and does 450NM take max effort?

First one that failed I thought perhaps I’d not given it enough, so second one I gave more..... and it failed after half the miles.

Annoying.

[123rover50]

Why do they need to be so tight?
My series wheel bearings are only finger tight and have a little backlash in them. Last for ever nearly.

[goingbush]

Why do they need to be so tight?

stupid pretensioned unit wheel bearings , I HATE them with a passion , give me dual tapered rollers any day.

heres a knackered one from my Iveco, $600 in Iveco box, $160 in SKF Box $80 in Febest box


https://scontent-syd2-1.xx.fbcdn.net/v/t1.0-9/36034482_1741501105931672_3959148613489131520_n.jp g?_nc_cat=0&oh=93683177a2936e92ceb813d9a1b3f734&oe=5BE63571

[goingbush]

Yeah it’s loads isn’t it.

How long is that torque wrench of yours and does 450NM take max effort?

First one that failed I thought perhaps I’d not given it enough, so second one I gave more..... and it failed after half the miles.

Annoying.

My 450Nm torque wrench is a Meter long, i'm 100kg & have to sit on it & bounce

[fitzy]

So 100 kg x 1 metre equals how many nm?

[ballbag]

100

[ozscott]

What were symptoms of the failure Ballbag? Cheers

[fitzy]

That’s what I thought.
Is 450 kg at 1 m 450nm?
Or 45kg at 10 metres?

[bee utey]

So 100 kg x 1 metre equals how many nm?

One kg exerts a downwards force of 9.81 Newtons. Equation: F = ma or F = mg, where m = mass and a = acceleration, and gravity's acceleration "g" at the earth's surface is 9.81m/s². So 981 or 1000Nm in round figures.

[101RRS]

100

Hmm no - 1kg = 9.8n so 100kg at 1m is 980NM

[ballbag]

Yeah, sorry that’s right.

[ballbag]

What were symptoms of the failure Ballbag? Cheers

Just the noise.

With wheel off ground the freeplay was obvious.

[Pedro_The_Swift]

So the D2 has just one(per wheel) of those pretensioned bearings?

[PhilipA]

The D2 has unitary hubs.
All the torque does is stop the hub from moving on the splines.
Maybe the OP sat in water for a while or the hub was faulty when fitted.

Regards Philip A

[donh54]

My 450Nm torque wrench is a Meter long, i'm 100kg & have to sit on it & bounce

Bouncing will totally negate the accuracy of the torque wrench.
Amongst the very first things I was taught about torque wrenches, was that they are designed to be used with a steady pull/push
They mostly rely on the deflection of the handle or an internal bushing, to measure the amount of force being applied, and a bounce, or shock loading, will alter that deflection outside the known parameters.

[Hoss]

I’m no help to you ballbag, but enjoyed looking up the song! [emoji3]

[Bohica]

100

100Nm

[RobMichelle]

100NmSo what is the consequence of not doing it up to that amount of torque

[PhilipA]

So what is the consequence of not doing it up to that amount of torque

The hub may then move on the splines fretting them in that great Defender tradition.
Seriously The exact torque is not that important.
IMHO just let the rattle gun rattle for a while.
Regards Philip A

[Kaaaiju]

I do my Hubs up with an Milwaukee impact gun,never had an problem

[donh54]

As long as you know what torque the gun is set at, that's okay.
Exact torque is usually so that you don't over-stress the threads or the strength of the fastener. Rather important, I'd say.

[PhilipA]

Exact torque is usually so that you don't over-stress the threads or the strength of the fastener. Rather important, I'd say.



It's a bloody big thread and a bloody big nut so there would be not much chance of overstressing it unless you had a bloody big rattle gun. I would doubt that mine would get to 450NM but probably in the high 3s. I have used the same hub and same nut so I stop when near the original position which is indicated by the indent in the collar of the nut which you have to bash out to undo.
New hub and nut would be more problematic.
Regards Philip A

[DeanoH]

Have I read this right ?, the original wheel bearing fails so the hub is replaced; this new hub fails and is again replaced and has now failed again ?

It could be a quality issue with the replacement hub(s), I assume you've followed this up with your supplier ? is there a known issue ?, presumably not as you've posted here.

So that leaves us with three hub failures in a very short time, the first can possibly be written off to 'normal wear and tear', the second to 'Murphys Law' or just **** out of luck but a third ?, no way, I reckon there's got to be something else going on here. But what ?

How about a bit of vehicle history/usage etc what's happened that may have bought this rash of bearing failures on ?

Just 'reaching' here, is the front axle bent backwards like when you hit a stump/rock hard and skewed the steering geometry/setup which could be compensated for with tie rod adjustment but cranking the stub axle at an extreme angle when at full lock putting uneven strain on the bearing causing it to prematurely fail ? As I said reaching here but just trying to figure out a cause for multiple bearing failure on the one wheel.
Your Disco isn't one of those stunt cars that drives along on two wheels on the one side ? :) or you drive hard to get your bearings warm and then go and park the front side of the vehicle in the dam ? :)

Just trying to come up with a reason for your multiple failures. I don't reckon nut torque unless grossly overdone is an issue here.

My two bobs worth.

Deano :)

[rangieman]

Which location is the one that is failing ?

Maybe think about where you drive if it is a L/H bearing that is giving you grieve .

The L/H wheel`s are all ways running on the worst part of the road you could also have a alignment issue with something bent but you would be scrubbing tyres [wink11]

[justinc]

What tyre profile are you running?

[ballbag]

LH front.

This is the second bearing to fail. The original was replaced but was not shagged (long story). Bearings on other three corners still original. So no originals have failed.

Supplier honoured first failure with warranty. Apparently second bearing came from a different run so bad batch ruled out. Can only take their word for that.

Have not yet pulled second bearing off vehicle. Will not get to that for about a week. Will report findings when I do.

Vehicle is 4.0 V8 auto with 300k on clock. City car until 200k. Touring 4WD since then, travels at GVM. 31” tyres on 16x8 P38 wheels.

Has seen deserts, sand, mud, rocks, water, snow etc but nothing outrageous. Has never been stuck, pullled or winched to give you an idea.

Alignment is good, always has been. Has not taken any knocks big enough for me to remember.

Some pulsing in the brakes. That or the nut being over or under torqued are all I can come up with.

Thanks for the input. Happy to hear any ideas as I’d rather not waste another few hours and few hundred bucks doing it again.

[p38arover]

Hmm no - 1kg = 9.8n so 100kg at 1m is 980NM

So to put 490 newton metres torque on a 1 metre breaker bar would require not 490kg force but 50kg force.

Maybe the OP was over-torquing the bearings.

[ballbag]

Yes, the more I think about it the more I believe so.

[donh54]

You said they weren't Britpart. Were they genuine LR, or aftermarket?

[PhilipA]

I spent some time looking for a cutaway.
I don't know whether the bearings are tapered roller or ball bearings, however whichever they are they come from the factory pre tensioned.
You would have to really overdo the torque to distort the spacer enough to over-tension the bearing.
However anything is possible!
I mean another term for 450NM is a "****load" and 650 on the back is a "big ****load"
I have to say That I still think they were faulty from the start or have been wet.
Why not try a second hand known good bearing to see how it lasts?

141685
Regards Philip A

[goingbush]

A really stupid cheap and nasty design that came about because mechanics are not mechanics any more. We can't have "Service Technicians" getting dirty hands can we .
Packing and adjusting tapered rollers is just not on , Who knows what hazardous stuff in in grease ? !!

[justinc]

Impossible to overtorque them.. they are assembled pretorqued, lubed and ready to bolt on. The torque setting for the nut is simply to clamp the bearing inner race, which is part of the internal splined drive surface, hard to the CV bell to prevent spline fretting, same as any front wheel drive car.

[discorevy]

A really stupid cheap and nasty design that came about because mechanics are not mechanics any more. We can't have "Service Technicians" getting dirty hands can we .
Packing and adjusting tapered rollers is just not on , Who knows what hazardous stuff in in grease ? !!


Have to disagree with that,
From factory you can expect around 300000 k before replacement normally
How many repacks / axle seals/ swivel hub bearing/gaskets / bush/ grease / bearing replacements in that time at what cost in time / labour?
In my view this is a much better design
Just don't skimp on rubbish parts when it's time for replacement, only problem is finding quality parts these days
I still consider myself a mechanic, but you can call me what you like.[thumbsupbig]

[ballbag]

You said they weren't Britpart. Were they genuine LR, or aftermarket?

Aftermarket, sourced in Aus but can’t recall brand sorry. Price was about $350.

[ballbag]

Impossible to overtorque them.. ...The torque setting for the nut is simply to clamp the bearing inner race....hard to the CV bell to prevent spline fretting .....

So you reckon no chance of deforming the inner race if over-torqued?

[justinc]

So you reckon no chance of deforming the inner race if over-torqued?

No possibility at all as the inner race IS the splined drive area and 'cast' as such. Even a 100t press couldnt..

[Cannon]

You need the ones with Timken bearings.

I bought a cheap one $350 & it failed really quickly.

[justinc]

YouTube (https://youtu.be/21zKFWSrDaY)

This is the same design hub.

[AK83]

Have to disagree with that,
From factory you can expect around 300000 k before replacement normally
How many repacks / axle seals/ swivel hub bearing/gaskets / bush/ grease / bearing replacements in that time at what cost in time / labour?
In my view this is a much better design
Just don't skimp on rubbish parts when it's time for replacement, only problem is finding quality parts these days
I still consider myself a mechanic, but you can call me what you like.[thumbsupbig]+

+1 (other than the mechanic comment).

1/. (i.e) I'm not a mechanic!(I'm a truck driver), but sometimes you gotta do what you have to to keep moving, so pretending to be a mechanic and getting hands dirty isn't an issue for me.
But having done brothers D2 a while back and more recently doing my D1 .. give me the D2 option every time.

2/. Time! takes about one hour or maybe a tad more to do the bare minimum bearing replacement on the D1 .. took about 30mins to do brothers D2.
On the D1 tho, it doesn't into account the stub axle .. while not a lot more time to do that too, just the added stuffing about with more parts than the D2 all in one design type.
If you're not a do-it-yourselfer type, then time becomes an issue on the cost of the repairers time too.
While you could get away on a D1/Defender/RRC type assembly just doing the bearings and seals, more often then not, there will be another issue somewhere else down the track, whether it's the drive member is worn, or the inner bearing for the CV or spacer collar .. or whatever.
So D2 bearings initially seem more expensive than the cheapest option for the D1/Def/RRC assembly type, but if you want to renew the entire assembly type, the total cost(of parts plus the mechanic/technicians, time) far surpasses the much better D2 design.

I reckon we could do all four D2 bearings in the time it'd take just to do the one front complete assembly on a D1(granted that the rear's are quicker to do tho).

I've been looking at all my bearing/hub/CV/seals/etc bits for a few days now trying hard to motivate myself to get stuck into it all ... I'm just not very good at self motivation tho! [tonguewink]

[ballbag]

No possibility at all as the inner race IS the splined drive area and 'cast' as such. Even a 100t press couldnt..

Makes sense. Cheers.

[justinc]

Makes sense. Cheers.

Did you watch the vid above?

[ballbag]

I missed it earlier but have just watched it. Was there something in particular I should have picked up on?
I was reasonably familiar with the construction already but obviously not expert.

[justinc]

I missed it earlier but have just watched it. Was there something in particular I should have picked up on?
I was reasonably familiar with the construction already but obviously not expert.

No just thst the degree in which the nut is tightened has no bearing (😅) on the preload...

[AK83]

ie. I think what JC is saying .. is that you can't really stuff up the install.

so most likely reason for failed bearings will then simply equate to either manufacturing faults(or just plain dumb luck) or some kind of other installation anomaly.

When we did brothers, about the only real way to stuff up at install would be if zero care was taken during the installation of the ABS sensor, and possibly dirt had fallen into the access hole prior to fitting the sensor?

[ballbag]

Removed bearing yesterday and compared to new cheapo sourced from UK (box branded ‘Vorderkante’).

Noticed old bearing had no o-ring or gasket sealing ABS sensor. New bearing has an o-ring for the probe and 2 metal gaskets for the mount.

Also jogged my memory of the first replacement not having a rubber seal for the assembly itself to seal against the knuckle. That bearing went back to supplier and warranty was honoured and they either didn’t notice or didn’t care.

Waiting on some new brake rotors to arrive before torquing up new axle nut.

Hopefully this one makes it through winter.....

[donh54]

Removed bearing yesterday and compared to new cheapo sourced from UK (box branded ‘Vorderkante’).
....

So you're replacing a failed non-genuine part, with another non-genuine part?
There are some parts I just don't bother with non-genuine. Things like steering and suspension are prime examples. Wheel bearings and seals, I will try for genuine or (true) OEM components, as per the earlier comment regarding Timken bearings.

[ballbag]

Differing circumstances I’d say.....

The old Disco - it’s a bit of an experiment. Happy to wing it in this instance.

The V35 Skyline or the VC Commo - no way, genuine or better.

The LS1 ute - do a burnout, worry about it later.

Anyway, think first replacement was sold as OEM and came with some knowledge of sales history. I keep a detailed log for all my vehicles and I’m a bit crook on myself for not having recorded the brand of the failed units.

[Roverlord off road spares]

Removed bearing yesterday and compared to new cheapo sourced from UK (box branded ‘Vorderkante’).

Noticed old bearing had no o-ring or gasket sealing ABS sensor. New bearing has an o-ring for the probe and 2 metal gaskets for the mount.

Also jogged my memory of the first replacement not having a rubber seal for the assembly itself to seal against the knuckle. That bearing went back to supplier and warranty was honoured and they either didn’t notice or didn’t care.

Waiting on some new brake rotors to arrive before torquing up new axle nut.

Hopefully this one makes it through winter.....

Front hubs do not have an O ring seal they have a seal inside on the axle into the tube, Rear hubs have an O ring
The O ring for the sensor is part of the sensor kit and comes with a sensor, the reason you wouldn't find one on a bare hub assembly, but your replacement one obviously included one .

[ballbag]

Front hubs do not have an O ring seal

Of the three I’ve now fitted, two did. Just sayin’.

Re ABS o-ring - makes sense. Nice touch with the metal gaskets on this one though.

[Pedro_The_Swift]

:ttiwwp:
too late?[bighmmm]

[Roverlord off road spares]

Of the three I’ve now fitted, two did. Just sayin’.

Re ABS o-ring - makes sense. Nice touch with the metal gaskets on this one though.

as the front and rear bare hubs are identical often an O ring is included for use if fitting on the rear axle. the only diffencence is when you purchase a dedicated hub which includes the sensor wire then they are different part numbers as the sensor wires are different lengths.

[grh]

Is not 100 kg metre equal tp 980 Newton metre?

[ballbag]

Yes[emoji106]

[RangieBoy]

So 100 kg x 1 metre equals how many nm?

You may be confusing Nm with kg.
A 1 kg force is equal to a force of 9.8 Newton, so (your weight of) 100 kg x 9.8 = 980N
Multiply this by the 1.3 meter bar and you get a torque of approx 1300 Nm
No wonder your bearing didn't last. Far too overtight.
For the correct torque, 490 Nm is approx 50 kg (490 divided by 9.8) at 1 metre.
For the 1.3 m bar you would need approx 38.5 kg to provide 490 Nm.

Hope this helps.

[RangieBoy]

First time reply. Second attempt as may have got the first try wrong.

A force of 1kg as equal to a force of 9.8 Newton metre.
So your weight of 100 kg is equivilant to 980 N
Multiply this by your 1.3 metre bar and you have a torque of approx 1300 Nm.
No wonder your bearing failed. Far too much tightening torque.
For a torque of 490 Nm you need a force of 50 kg at 1 metre (490 divided by 9.8 = 50)
With your 1.3 metre bar, you would need to apply a force of 38.5 kg (at 1.3 metre) to give you the correct 490 Nm to tighten the nut.

[justinc]

First time reply. Second attempt as may have got the first try wrong.

A force of 1kg as equal to a force of 9.8 Newton metre.
So your weight of 100 kg is equivilant to 980 N
Multiply this by your 1.3 metre bar and you have a torque of approx 1300 Nm.
No wonder your bearing failed. Far too much tightening torque.
For a torque of 490 Nm you need a force of 50 kg at 1 metre (490 divided by 9.8 = 50)
With your 1.3 metre bar, you would need to apply a force of 38.5 kg (at 1.3 metre) to give you the correct 490 Nm to tighten the nut.

......except tightening the nut has no effect on bearing preload eith these hubs....

[ballbag]

Besides, I weigh 75kg and I’m pulling on the bar, not pushing and probably centering that force at about the 1 metre mark....uneducated guess says I might have put 600 on the second bearing, maybe 400 on the first. Undoing them was not an issue.

And as stated earlier there does appear to have been some, however small amount, of water/dirt/mud ingress.

And there was a slight pulsing through the brake pedal, but whether that’s cause or effect I don’t know.

Really, I’m none the wiser.

[DazzaTD5]

Good grief.... should I even add to this thread?

As JustinC has mentioned, quite a few times, and other comments on this or that bearing setup
IMHO....
*The bearing hub assembly on a D2 is ready to bolt up, no pre-loading is done during installation, just bolt up the retaining bolts at the back.
*The centre nut is just to retain the axle, as mentioned to reduce the fretting on the splines, put some anti-seize on the splines, so in another 200 - 300K if the bearing hub assembly fails it will be easier to remove.
*The complete bearing hub assembly on a D2 is a better setup over the earlier Land Rover method, such as on a Defender. Certainly if you have a failure in the bush its easier to change, no chance of dirt ingress, no seal to fit, no grease to pack etc etc.
*I stick with genuine when it comes to bearings UNLESS the OEM states SKF, Timken, (known good brands) etc etc

*Its NOT like some of the lesser brands of vehicles out there that have a similar setup BUT the retaining nut in the centre (often bigger) is used to pre-load the bearing/hub assembly, from memory toyota hilux and hiace have this setup.

P.S the OP has now replaced more D2 bearing hub assemblies than I prolly do in a year, they really are reliable.
AND, for goodness sake just rattle up the centre nut and forget about the torque equation
Torque - Wikipedia (https://en.wikipedia.org/wiki/Torque)