Balljoint and axles, how much is this gunna cost?

[Kestas]

Originally Posted By: onion

Originally Posted By: Kestas
Bearings, including CV joints, are not replaced in pairs. When that kind of work is done under warranty, it is not authorized to replace in pairs unless both sides are diagnosed to be bad (which happens only rarely).

They aren't wear items in the traditional sense of "wear". They either work or they're bad.


So if a front wheel bearing (let's say on a '94 Chevy Corsica) fails at 170,000 miles, then you would only replace the failed bearing? 'Cause the other might have quite a lot of life in it?

What if the 'other' bearing was slightly loose (only slightly), but otherwise smooth and trouble-free?

Let's see... '94 Corsica... 170K... one bearing fails. The technical answer is the same as I previously stated. That bearing must be replaced.

As far as the other bearing being slightly loose, you still have to take each bearing on its own merits. You have to ask why the bearing is slightly loose. This goes for sealed hub units as well as serviceable tapers. Like I said, bearings don't wear in the traditional sense of wear. I've had to argue this point many times with people who intuitively insist that bearings can wear. If a bearing shows wear it is bad and must be replaced.

 

[onion]

Quote:
You have to ask why the bearing is slightly loose.


You gotta help me out here... I'm kinda slow. It's loose because it has 170000 miles on it?

So do you think it needs to be replaced?

 

[Kestas]

Dig deeper. Ask yourself what is it about the high miles that makes it loose? Remember, the bearing - if still healthy - should have no wear on the active surfaces. In fact, they should still have the original honing marks.

For the third time, bearings don't wear in the traditional sense. Ball joints wear, pads and rotors wear, cylinder walls and piston rings wear, valve guides wear, and seals wear. But roller bearings don't wear in healthy normal use as long as the grease is still healthy.

If the bearing is loose, inspect it and reset the preload. If it's a sealed hub unit, it has lost preload, premature failure is imminent from the rollers running in what is called "truncation" (meaning they are riding on the shoulder of the raceway, which isn't good), and the bearing must be replaced.

 

[onion]

Originally Posted By: Kestas
Dig deeper. Ask yourself what is it about the high miles that makes it loose? Remember, the bearing - if still healthy - should have no wear on the active surfaces. In fact, they should still have the original honing marks.

For the third time, bearings don't wear in the traditional sense. Ball joints wear, pads and rotors wear, cylinder walls and piston rings wear, valve guides wear, and seals wear. But roller bearings don't wear in healthy normal use as long as the grease is still healthy.


Metal fatigue?

That's the best I can do. If that isn't right, then you're just going to have to spoon-feed me... or let me wallow in my own ignorance.

Quote:
If the bearing is loose, inspect it and reset the preload. If it's a sealed hub unit, it has lost preload, premature failure is imminent from the rollers running in what is called "truncation" (meaning they are riding on the shoulder of the raceway, which isn't good), and the bearing must be replaced.


Sounds like I should replace that other bearing one of these days when I have time.