Fretting corrosion on axle splines?

[89Ru]

15 ton press couldn't budge a '97 obw front axle, stuck in hub splines (210k miles on mid-atlantic salty roads)

Finally hammered out with an air tool at the same machine shop for $50

 

A look into the hub reveals severe black corrosion, very hard, the new axle won't go in and kroil doesn't seem to touch it.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=54444&highlight=spline+corrosion&page=3

 

Never greased the splines before, think permatex anti-sieze would work or do I need better grease?

 

I'm using a steel scraper to get between the splines, not too successfully, probably time for a new hub.

[Fairtax4me]

Get a triangle file and try that?

 

I've had to deal with some pretty rusty hubs living here but some of the horror stories I read on this forum are just insane.

 

Using any kind of high temp grease or anti seize is better than nothing. Hell I bet even thread lock would work!

[89Ru]

chiseled the chunks out with a philips screwdriver :-\ still won't go in, urge to use a hammer, but if it only goes half way, its back to the machine shop.

 

triangle file is a great idea

 

the black chiseled stuff is magnetized

 

what I really need is a dentist

 

I'll try bearing grease, or maybe crest toothpase, tartar formula hehe

[Fairtax4me]

A short lesson on "Black rust" that I found. Pretty interesting stuff. Found in nature it's known as Magnetite. Easily synthetically produced by mixing sodium hydroxide and Iron. Apparently it inhibits formation of regular red rust, is used in cosmetics for black coloring, and inside TV tubes.

Assuming that these people know what they're talking about. http://www.finishing.com/95/49.shtml

 

And then there's some stuff on Wikipedia, which should always be read with a grain of salt. http://en.wikipedia.org/wiki/Iron(II,III)_oxide

 

If it inhibits further rusting, maybe you should leave it in there?

[frag]

I second using a triangular file of the right size. That's what I did when I replaced my front axles and it worked. A lot of salt here also.

Good luck!

[89Ru]

Fairtax, you nailed it, magnetite. Some fancy chemistry going in my hub for sure. No common red rust in there, just black.

 

Triangle file did the trick

 

Axle went in with minimal effort, greased up with high temp lithium.

 

 

Next tool on the list: air hammer

 

Thanks for the consult

[johnceggleston]

Triangle file did the trick

 

Axle went in with minimal effort

 

 

i don't mean to be dense here but how did you use the file, what did you clean up? how large a file did you use?

 

thanks.

[Fairtax4me]

Fairtax, you nailed it, magnetite. Some fancy chemistry going in my hub for sure. No common red rust in there, just black.

 

Triangle file did the trick

 

Axle went in with minimal effort, greased up with high temp lithium.

 

 

Next tool on the list: air hammer

 

Thanks for the consult

 

Glad it worked for you! I usually just run a wire brush through them a few times to take care of corrosion and scale in there. Never had to use a triangle file for that specifically, but it seemed like it should work.

Not sure how you ended up with "black rust" in there, but Id have to guess road salt and heat had something to do with it.

[89Ru]

i don't mean to be dense here but how did you use the file, what did you clean up? how large a file did you use?

 

Had a torn inner boot on the front left half shaft, so I replaced the axle...sorry should have said that first. Standard red rust corrosion on the inner splined transmission stub, nasty black stuff on the outer splined hub, like rock, now identified as 'magnetite'

 

http://i444.photobucket.com/albums/qq166/89ru/EJ25/DSCF2692.jpg

 

These are the chunks chipped out of the hub splines with a screwdriver, tool abuse but nothing else fit the splines that nice.

http://i444.photobucket.com/albums/qq166/89ru/EJ25/DSCF2689.jpg

 

Pictures don't really show it, need a macro lens to get enough detail.

 

To remove the remaining corrosion buildup on the hub splines I used a triangular file, from a needle file kit from harbor freight. The file fit into the hub splines to reduce the corrosion that was preventing the replacement cv axle from inserting into the old hub. The needle file wasn't an exact fit in the splines, much slop, but got the job done.

[johnceggleston]

Had a torn inner boot on the front left half shaft, so I replaced the axle...sorry should have said that first. Standard red rust corrosion on the inner splined transmission stub, nasty black stuff on the outer splined hub, like rock, now identified as 'magnetite'

 

http://i444.photobucket.com/albums/qq166/89ru/EJ25/DSCF2692.jpg

 

These are the chunks chipped out of the hub splines with a screwdriver, tool abuse but nothing else fit the splines that nice.

http://i444.photobucket.com/albums/qq166/89ru/EJ25/DSCF2689.jpg

 

Pictures don't really show it, need a macro lens to get enough detail.

 

To remove the remaining corrosion buildup on the hub splines I used a triangular file, from a needle file kit from harbor freight. The file fit into the hub splines to reduce the corrosion that was preventing the replacement cv axle from inserting into the old hub. The needle file wasn't an exact fit in the splines, much slop, but got the job done.

 

thanks, the pics helped explain it. for some reason i had a picture in my mind of rectangular splines and i couldn't imagine how a triangle file fit or helped.

 

glad you got it.