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Wheel Bearing Hub Knuckle Troubleshooting


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Hello, I am back.  98 OBW 240K.  This is how it started.  Out of nowhere the wagon felt very sluggish like something was holding it back. Drove it for a few weeks thinking  it was the transmission and knowing my duty c solenoid is busted I was just waiting the clock out. Then it happened smoke started pouring out of front driver side wheel well.  Now I am thinking stuck caliper.  So I pulled the wheel off and started troubleshooting.  Sure enough the caliper is frozen solid.  Knocked it off with a dead blow hammer and then I saw a torn ball joint  along with a torn axle boot.  That forced me to tear apart the front driver side suspension to start getting everything fixed.  Here is my question.  When I unbolted  the knuckle and pulled the axle out of the transmission the hub just fell out of the knuckle.  Does this mean the hub was also spinning in the knuckle?  I can push the hub back into the knuckle and get it to almost site perfectly.  The shaft of the hub does not look worn but the race is still on so I can't be 100% sure.  What do you guys think?  Could the stuck caliper have caused this? The wheel did not wobble at all before I took this apart.  Anyone ever see the two units just fall apart?  I attached a pic so you can all see this wonderful mess.

post-13518-0-90697800-1389842184_thumb.jpg

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woah elephant smoke batman, that's crazy!

 

yeah you need a new wheel bearing, the hubs never come out like that, never seen or heard of that happening.

 

make sure you reboot the axle, aftermarket axles sucks really bad, clean, regrease, and reboot the OEM axle at all costs.  or buy a used one at a yard and reboot it if you don't want your axle for some reason. 

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The way to check a hub (if it falls outta the race it's way bad) is to look at the fine lines on it wgere it goes into the race. Fine scratches along the length where it was pressed in/out are fine, any scratches that go around or any discoloring shows the bearing race has been moving on the hub.

 

It's not so much that if it rotates the rotation will damage the bearing, but that if it rotates the inner race will not be held perfectly centered and the balls/rollers and race contact points will be overloaded, too few balls/rollers will be taking all the load. When they get overloaded they fail quickly.

 

Also, if one race spins and the other does not spin with it, the face where the races contact each other will wear and the bearings will at first get too much preload (axle stretch acting like a spring), then as it wears they'll get too little.

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  • 2 weeks later...

Does this make any sense? I just finished the job on the front Driver side wheel.  Caliper, Axle, Pads, Rotor, bearing and hub along with a break bleeding.  I am going down the road 40MPH  and smoke is now pouring out of the rear driver side wheel well.  I am not a real big believer in coincidences. Any ideas? 

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Does this make any sense? I just finished the job on the front Driver side wheel.  Caliper, Axle, Pads, Rotor, bearing and hub along with a break bleeding.  I am going down the road 40MPH  and smoke is now pouring out of the rear driver side wheel well.  I am not a real big believer in coincidences. Any ideas? 

Did you overfill the brake fluid reservoir? I remember a post here a while back saying too much fluid in his reservoir caused his caliper piston to stick without retracting. He took out some fluid and the piston worked fine afterward.

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Hello,  I did make sure it was at the full line.  I pulled the wheel off and the caliper was frozen.  I am going to put on a reman this weekend.   One thing to note.  About 6 months ago I rebuilt every caliper. I have around 1K miles since.  Wonder if that kicked this off.  I will report back when done.

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Did you overfill the brake fluid reservoir? I remember a post here a while back saying too much fluid in his reservoir caused his caliper piston to stick without retracting. He took out some fluid and the piston worked fine afterward.

What that poster said was, when the brake fluid was a little over the full line, he had caliper piston problem. After he reduced the fluid level to about 3/4 full and pushed the piston back, the problem went away. His experience was that too much fluid was not a good thing.

Edited by vasy
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I did drop the brake fluid some but then the brake light went on.   In the end is was several things on a 16 year old wagon.  I would have bet it was the transmission but it was two stuck calipers, axle, ball joint, wheel bearing, hub and a rotor that all contributed to the problem.  I have fixed all of it and if I had to use a shop I think this OBW would have headed to the bone yard.  Thanks for the guidance and help.  This summer is a duty c solenoid and clutch pack.  I am going to finish a thread that was started back in 07 by someone on this forum.

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  • 1 month later...

The way to check a hub (if it falls outta the race it's way bad) is to look at the fine lines on it wgere it goes into the race. Fine scratches along the length where it was pressed in/out are fine, any scratches that go around or any discoloring shows the bearing race has been moving on the hub.

 

It's not so much that if it rotates the rotation will damage the bearing, but that if it rotates the inner race will not be held perfectly centered and the balls/rollers and race contact points will be overloaded, too few balls/rollers will be taking all the load. When they get overloaded they fail quickly.

 

Also, if one race spins and the other does not spin with it, the face where the races contact each other will wear and the bearings will at first get too much preload (axle stretch acting like a spring), then as it wears they'll get too little.

 

I have one front wheel bearing going out on both of my cars and have a couple questions for those with more experience on here:

Should I get a new hub from Rockauto (Dorman for $24)?  One of the bearings that is loose and noisy again was just replaced a couple thousand miles ago.

How do they normally fail?  They obviously get loose, which causes some wandering and brake pad wear, and squeak occasionally.  Do they just get so sloppy as to be undriveable?  Do they suddenly lock up solid?  Do they eventually make a ton of noise?  Just curious, I'm sure someone out there has driven on a bad wheel bearing without noticing until something really bad happens.

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Who replaced the one that is noisy again after a few thousand miles?

Either the hub was badly damaged and re-used, or the knuckle is shot, or it was done wrong (axle nut tightened with the wheel on the ground? Nut not tightened enough, or it loosened?)

 

Are you sure it is the same one?

 

I would be ready with a new hub in case it is needed.

 

I have done fronts and backs, the front one never got hot or loose, just made noise for thousands of miles.

The rear got a bit loose after driving on it for a long time, I was wearing ear plugs for a while it was so loud.

 

You don;t want to drive on a loose one...

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Who replaced the one that is noisy again after a few thousand miles?

Either the hub was badly damaged and re-used, or the knuckle is shot, or it was done wrong (axle nut tightened with the wheel on the ground? Nut not tightened enough, or it loosened?)

 

Are you sure it is the same one?

 

I would be ready with a new hub in case it is needed.

 

I have done fronts and backs, the front one never got hot or loose, just made noise for thousands of miles.

The rear got a bit loose after driving on it for a long time, I was wearing ear plugs for a while it was so loud.

 

You don;t want to drive on a loose one...

 

I removed the spindle/hub and took it to a friend's shop who did the pressing.  It was very difficult to get the bearing out of the spindle, so maybe that's bad.  I am trying to get some replacement spindle/hub assemblies, for spares if for no other reason.  For what it's worth he's worked on a lot of Subarus and says they basically always just get looser and looser until they're undriveable.

 

Yes, I tightened the spindle nut with the wheel on the ground, didn't realize I shouldn't do that at the time.  Thanks for that advice though.  It was torqued to spec and didn't loosen.

 

Yes, I'm sure it's the same one.

 

I plan on replacing the hub (since I can get a new one pretty cheap) and wheel bearing and see how it goes and try to find a good assembly in the meantime.

 

In the long run I plan on seeing if there's some larger or higher capacity bearing that could be made to fit, even if it required machining the hub.

Edited by pontoontodd
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When I did mine it was clear from the markings that the bearing did spin so I replaced it with a Dorman hub I found on Amazon for $40.  I also used a sealed bearing by GMB 758-0003 for my 98OBW "front bearing".  The last job only lasted 2-3 years.  I did use a new shop to press this last one in. I also just marked the camber bolt to avoid a front end alignment before I pulled off the knuckle.  I would have replaced the whole knuckle and tried but bone yard knuckles are 15+ years old and rusted with broken speed sensor and ball joint bolts.

Edited by msmithmmx
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if there's any question, i would get a used hub assembly and start with fresh knuckle and hub.

www.car-part.com

 

i'm not sure which (or both) can wear, but if they have been compromised it will eat up future new bearings.  one vehicle got a fairly consistent 17 and 18,000 miles between the three bearing changes before a new knuckle/hub assembly was swapped in.

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