repeated rear wheel bearing fail..any ideas?

[steveo3002]

even if they were rubbish bearings id expect maybe a years use or so...i think 6 weeks something is badly wrong

johnseat i know the torque figure and im doing them up as per the book ...just clutching at straws that im doing something wrong , its the only thing i can where it can go wrong , its pushed in carefully with an old outer race , never pushed on the center

 

[Spark plug]

Am I right in thinking there is a single double row bearing, not two single row bearings?

 

[Johnseat]

What's the torque setting?

 

[steveo3002]

Am I right in thinking there is a single double row bearing, not two single row bearings?

i think so , not too clued on bearing jargon , one peice with 2x sets of rollers inside , if you look at the youtube vids you can see them

 

[steveo3002]

What's the torque setting?

173ft lb ....skf had a note i think it was 90ft lb + 60 degs

 

[normspanners]

You would never damage the bearings by over torqueing them all you would do is damage the stub or the nut, From my experience, most garages now would run them up with a gun anyway, (even maindealers) so as to get their bonus.
back in the day ford maindealers ... fiesta full service was 15-20 minutes max.

 

[8ob]

In the absence of an obvious cause/diagnosis to this ongoing problem I am throwing rear tracking into the mix. Would small amounts of toe in/out put high enough axial loads on the bearing to cause failure? Its not a very large bearing in comparison to the fronts. Just thoughts

Bob

 

[steveo3002]

You would never damage the bearings by over torqueing them all you would do is damage the stub or the nut, From my experience, most garages now would run them up with a gun anyway, (even maindealers) so as to get their bonus.
back in the day ford maindealers ... fiesta full service was 15-20 minutes max.

thought as much

would you spin the drum while tightening?

my wrench is calibrated...but say im doing it 10% less , that wouldnt kill it would it ?

 

[normspanners]

Yes to spinning and No if it is still tight when you have come to undo them that good enough IMO, those nuts are self lockers anyway they are basically a stack of thin nuts in a cage that lock each other up when tightened. 10% is nowt

In the absence of an obvious cause/diagnosis to this ongoing problem I am throwing rear tracking into the mix. Would small amounts of toe in/out put high enough axial loads on the bearing to cause failure? Its not a very large bearing in comparison to the fronts. Just thoughts

IMO you would notice tyre scrub before brg failure .

 

[Johnseat]

You would never damage the bearings by over torqueing them all you would do is damage the stub or the nut, From my experience, most garages now would run them up with a gun anyway, (even maindealers) so as to get their bonus.
back in the day ford maindealers ... fiesta full service was 15-20 minutes max.

Never read as much nonsense in my life, no damage to over torquing bearings my backside, I'm bowing out of this one, can't help when such rubbish is being posted.
As for running up hub nuts with a gun at a main dealers, never seen that once and I've only ever worked at main dealers.

 

[PhillipM]

Even with modern double row bearings with an integral spacer you can still damage a bearing with over or undertorquing, just not as sensitive as the old angular pairs were, you'd have to heave on them though, under-torquing is more of an issue.

 

[steveo3002]

yes ft lbs

all i can think is try it tighter or not so tight

bearing push in on outer race only..clonks when home and uses a circlip so can only use the clip once its home

stub axle appears clean and undamage and never caused issues in the 40-50k we did before i disturbed the original drums

what else can i do ?

 

[PhillipM]

Check the the roundness and size of the drum where where outer race sits.

 

[steveo3002]

one more question....should i be putting a smear of grease on the stub axle or bolting it up dry (axle not threads)

 

[steveo3002]

roars this one with a gun and no spinning it

 

[rikrobson]

one more question....should i be putting a smear of grease on the stub axle or bolting it up dry (axle not threads)

Grease never hurts. If you grease tge thread though youll need to add a wee bit more torque or clean it

 

[normspanners]

Never read as much nonsense in my life, no damage to over torquing bearings my backside, I'm bowing out of this one, can't help when such rubbish is being posted.
As for running up hub nuts with a gun at a main dealers, never seen that once and I've only ever worked at main dealers.

HAHA!!


How is a hub nut going to damage a bearing race that is a flush face to face central connection with no spacer between the two inner bearing races you could put 20 tons of force in a press and not damage them so a 18mm nut slightly over torqued by the amount the OP is commenting will not put anywhere near that sort of force through the bearing races. the torque is a figure that is set to hold the two races together with enough force to not allow them to separate or turn in any situation, whilst maintaining the nut tightness under torqued would possibly be a problem, over torquing most certainly would not, it is not ME talking out of my backside sir, the torque figure is for the nut fastening not setting any bearing clearance and as said from visiting MANY garages rear and front CV hub nuts are done with a gun by MOST mechanics if they are 'fully tightened' nuts IE torqued to the nut or bolt max. Well if you have not seen that, I am afraid you are not very experienced, but having only worked at a main dealers that may be so. I visit MANY garages dealers and indies in my daily work, moting and see it done every day. So please do not state my comments are rubbish,
In fact could you explain how a BEARING that could easily stand 5x the maximum compressive force of a hub nut when using a press could be damaged by slightly over torquing it?

In fact just watch this video

roars this one with a gun and no spinning it

that is how 'MOST' garages do it, front cvs also ----- I am afraid.
BTW I am not condoning it------- but it is a fact.

Grease never hurts. If you grease tge thread though youll need to add a wee bit more torque or clean it

BTW that is the wrong way round more torque for a dry thread, less for a greased one.

 

[normspanners]

In fact could you explain how a BEARING that could easily stand 5x the maximum compressive force of a hub nut when using a press could be damaged by slightly over torquing it?

Anybody ??

 

[clift_d]

Check the the roundness and size of the drum where where outer race sits.

This can be a cause of early bearing failure. There's a known issue on some VWs that the bearing housings can oval with robust use, which can lead to premature failure of the outer bearing.. Also, as others have said, make sure that you're getting the right axle nut torque.

 

[steveo3002]

decided im goning to give this new one an extra heave on the bar ...obviously doing something wrong and thats the only step i can see that go wrong ?