Wonder what happened to this bearing?

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Parked when hot with the wheel on that side much higher than the other. Cooled, moisture condensed and the Jeep was parked too long afterward so corrosion set in.
 
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It’s likely trashed only on one side because the cup is fixed in the housing and doesn’t rotate. The worn area was probably at the top where the load was concentrated. It looks like fatigue failure from here, too many rough miles.
 

Kestas

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Can't tell why it failed without a complete examination of the bearing.

Material and manufacturing defects are rare. Bearings usually fail because of lubrication or installation failures.
 
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188K of rough service. Was that the right side carrier bearing race? The carrier tries to “walk out” away from the pinion especially under hard acceleration (tires spinning in sand). Cut the cage off the bearing and there probably will be corresponding wear on the inner bearing race. Bearings are a wear item…
 

Chris142

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188K of rough service. Was that the right side carrier bearing race? The carrier tries to “walk out” away from the pinion especially under hard acceleration (tires spinning in sand). Cut the cage off the bearing and there probably will be corresponding wear on the inner bearing race. Bearings are a wear item…
Both carrier bearings were like this. But one was worse. Don't remember which but you're explanation makes sense. All 6 bearings had some damage. Axle tubes loaded with fine metal sand.

No hard acceleration. I drive like a granny but lots of dirt roads. Always serviced with synthetic oil and never ran low.
 
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Not that great of a picture to make a judgment, but if it were mine...

Looks like low lube film, high loads, and mis-alignment or loose setting.

I would replace the bearing (obviously), go a step or two thicker on my lube selection, and error on the tighter end of the setting range tolerance. Maybe look and see if there is a P900 version of the bearing size you are using. That adds a feature to the rollers that makes them less likely to suffer from edge loading.

I was a Timken Engineer for the first 5 years of my career.
 
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Not sure about this diff but GM required a .002 additional shim for each shim pack at both carrier bearings (after snug fit & desired backlash) to ensure proper carrier bearing preload. Too loose or too tight can cause wear. It will be necessary to swab out the axle tubes to ensure cleanliness for a successful overhaul. I’ve used gasoline poured in the tube and then pushed a wadded rag toward the center section until the tubes shined like a clean gun barrel inside.
 
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Not sure about this diff but GM required a .002 additional shim for each shim pack at both carrier bearings (after snug fit & desired backlash) to ensure proper carrier bearing preload. Too loose or too tight can cause wear. It will be necessary to swab out the axle tubes to ensure cleanliness for a successful overhaul. I’ve used gasoline poured in the tube and then pushed a wadded rag toward the center section until the tubes shined like a clean gun barrel inside.

Your statement seems to contradict itself a bit...

If it is a shimmed assembly, then that shims should do the setting of the bearing pair, and the nut is used simply to snug things up, and does not effect bearing setting (neither preload or endplay). With out knowing if the bearing pair is direct mount, or indirect mount, and where the shim pack is, I can't tell you if the shim pack will tighten the setting or loosen the setting.

If the assembly is set with the nut through rolling torque and backing off, then the shim pack does nothing for the setting of the bearing pair. The setting is determined simply by the stack up through the position of the nut you are adjusting.
 
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