Differential Case Small Crack
Thread Starter
Instructor
Joined: May 2005
Posts: 222
Likes: 0
Differential Case Small Crack
I noticed a small crack in my differential case (assembly which ring gear mounts to). It is about 1/4 inch and extends from the corner of the window on ring gear side. I could not get a good photo to show. This appears NOT to be all the way through the case. I could not see it from the inside. My queation is, Is this usable? I've read inspection instructins which say to look for cracks from window to pin hole. This is no where near that bad but still I'm concerned. Any comments are appreciated.
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
If it is indeed a crack, then I would replace it regardless for peace of mind. But before you replace it, I would ask tracdogg2 or GTR1999 for their opinions on it - they are the differential gurus here.
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
Of course not.
Check your crack with the die check method. This is a red colored spray that contains a special creeping oil which intrudes the crack. Then this is washed off and then sprayed with kind of a white powder. The crack then shows up after a while because the residual red oil will wetten the powder. This proofs your crack if it is one.
If it only shows on one side, you might want to polish it before crack check with fine sandpaper. This just to assure your not checking a scratch only.
Of course, other crack check methods also work, like eddy current inspections etc, but this requires special equipment.
The die check spray should be readily available.
Good luck. Günther
Of course not.
Check your crack with the die check method. This is a red colored spray that contains a special creeping oil which intrudes the crack. Then this is washed off and then sprayed with kind of a white powder. The crack then shows up after a while because the residual red oil will wetten the powder. This proofs your crack if it is one.
If it only shows on one side, you might want to polish it before crack check with fine sandpaper. This just to assure your not checking a scratch only.
Of course, other crack check methods also work, like eddy current inspections etc, but this requires special equipment.
The die check spray should be readily available.
Good luck. Günther
Tech Contributor
Joined: Aug 1999
Posts: 15,156
Likes: 3,965
From: Connecticut, USA
The Dye Gunther mentions would work but I use brake cleaner and compressed air. The crack will stay wet after the surface is dried with the air.
There should be no cracks, I'd say 50% of the early eatons I get in to blueprint are cracked. These were from 65-68 in 69 -79 the design changed, they crack too but not nearly as much.
If you look up my threads on diff's I show all this stuff so you know what to look for and what your options are.
Good luck if you need any help let me know.
There should be no cracks, I'd say 50% of the early eatons I get in to blueprint are cracked. These were from 65-68 in 69 -79 the design changed, they crack too but not nearly as much.
If you look up my threads on diff's I show all this stuff so you know what to look for and what your options are.
Good luck if you need any help let me know.
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 330
From: Indy Indiana
Mine had a early eaton also like gary said.. i found that it had cracked also.. same place as usual. who knows when, i might have happened many owners ago...I found out when i tried to trade in my old rear end for a rebuilt one..
many of them are cracked and probably just as many are out there cracked and the owner does not even know...
just don't sidestep your clutch at 5000 rpm and it may last forever...
many of them are cracked and probably just as many are out there cracked and the owner does not even know...
just don't sidestep your clutch at 5000 rpm and it may last forever...
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
If you have a confirmed crack, you can impossibly keep on driving with it.
The difference here is that you know it is cracked, regardless if this is possibly normal etc. Once you know, that's it.
A crack check ( dye or whatever ) can be done with the cage installed.
Rgds. Günther
If you have a confirmed crack, you can impossibly keep on driving with it.
The difference here is that you know it is cracked, regardless if this is possibly normal etc. Once you know, that's it.
A crack check ( dye or whatever ) can be done with the cage installed.
Rgds. Günther
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