How much CV wear is too much?

[Mucci]

I keep watching videos of CV rebuilds and everyone is very vague on acceptable vs unacceptable CV joint wear. 
 

I got a set of axels second hand and don’t know their condition. I tore one down today to inspect. Let me know what you think of the wear:

 

The balls look flawless, which is a phrase I don’t think I’ve said before. 
 

I did notice one axel shaft has blueing at the end. Is this a treatment or from overheating? Any concern there? Splines look ok. 
 

 

Edited April 16, 2021 by Mucci

[Tommy]

For me that would be good to go. Blue is from heat treating.

[tzei]

^+1. Looks normal. 

[tech71]

^+2.  I have run far worse with no issues.

[Mucci]

Great, thanks for the feedback. I'll get the new boots and grease on there. 

 

So what are the "too far gone" wear characteristics to look for during a visual inspection like this where I don't know the part history? 

 

Also, is only one side heat treated? Is the axel directional because of that? I don't have it in front of me but I thought it was symmetrical. 

Edited April 16, 2021 by Mucci

[tzei]

Too far would be like twisted splines, balls pitted/ not shiny, cage cracked, inner parts grooves has pits/ bits missing.

 

Axles are not directional from new i think. Some ppl like to maintain direction when they are used. I have not and the world didn’t end.

[Chris_B]

A good diagnostic is radial play in an assembled axle. Any more than a few millimeters front to back will began to be felt in the steering wheel when putting a load on the axles (e.g., driving up a hill at a freeway speeds) as a slow shimmy (slow compared to a bent or out-of-balance wheel). If the shimmy goes away when you crest the hill, that likely indicates that you have a sloppy CV. These can last for a long time before the slop reaches a critical mass.

[Chris_B]

Just now, Chris_B said:

A good diagnostic is radial play in an assembled axle. Any more than a few millimeters front to back will began to be felt in the steering wheel when putting a load on the axles (e.g., driving up a hill at a freeway speeds) as a slow shimmy (slow compared to a bent or out-of-balance wheel). If the shimmy goes away when you crest the hill, that likely indicates that you have a sloppy CV. These can last for a long time before the slop reaches a critical mass.

Oops. I was thinking of the effect on a front driver (my daily driver is a Jetta TDI). I don't know how a sloppy CV would feel on a rear driver, because I have always kept mine tight on my 02.