Gentlemen, take a look at this wierdness...odd "crack" in diff housing

[Scott Vincent]

Got the axle housing emptied out for rebuild and was cleaning it up this morning. After some cleaning, I noticed the "cracks" youʻll see in the pictures. Now looking at the drivers side, that one looks like itʻs there for a reason, cast during manufacturing. The passenger side however, definitely does not. Now itʻs on the outside of the area and behind where the bearings and races will be. Because of this, I donʻt think itʻs a detrimental things. Iʻm thinking of just filing or die grinding burrs down and continuing on with the build. Iʻm asking for confirmation that this diff housing isnʻt fu^&ed and my plan is sound. And maybe any guesses as to wtf happened to do this. I think this is simply axle passthorugh area, thats why Iʻm thinking Iʻm ok.

 

[Big Ray]

What axle is that? I don't recall ever seeing that before...

 

[Scott Vincent]

GM 8.5" 10 bolt

 

[nvrenuf]

In pic 1 showing the entire inside, are you talking about the line that runs vertical from the bottom towards the top of the housing? If so, that looks like a casting line. It appears to be raised, a crack wouldn’t be unless the parts are shifting apart. You probably do not have any evidence of a leak there on the outside, do you?

 

[Midnightmoon]

I was just going to ask the same question, any evidence of a leak? If not, it will probably be OK once it is reassembled.

 

[Big Ray]

I think he's talking about the notch the bearing race sits in...

 

[Scott Vincent]

No...Iʻm not talking the seat for the race. Let me see if I can take the picture and circle the areas Iʻm talking about.

 

[Scott Vincent]

Here..this is from outside and one is from inside.

 

[Scott Vincent]

Alright, my buddy put me in touch with an axle guy...Iʻve been right all along. Itʻs a non-issue because all that area is is shaft pass-through. All I need to do if I want to feel good about it is what I said...light deburring and continue. Sorry to bug you guys. Iʻll leave the post here in case anyone else runs into this.

 

[bucket]

Alright, my buddy put me in touch with an axle guy...Iʻve been right all along. Itʻs a non-issue because all that area is is shaft pass-through. All I need to do if I want to feel good about it is what I said...light deburring and continue. Sorry to bug you guys. Iʻll leave the post here in case anyone else runs into this.

You didn't bug anyone useful info is useful info.

 

[DoubleDingo]

You didn't bug anyone useful info is useful info.

^^^THIS^^^

 

[84c10Tony]

Hiya!,
Good catch for info and thinking.
Looks like basic casting error to me and doesn't hurt anything.
If it needed my piece of mind, for my piece of mind later, I would think of something to fill it in, JB weld comes to mind.
I have had that "opportunity" maybe a half dozen or so times in 30-40 years.
Sometimes it was a "just in case" for my my piece of mind, and sometimes it was a crack/broken etc., maybe once it was just for fun.