Salisbury diff housing failures

Similar failures can occur after buttressing a bone fracture such as a humerus or femur IF the buttress plate is not removed after fracture has healed. I had mine removed after 12 months for this reason. Like steel tubes bone is flexible. Further fractures will occur either side of the stiffened section if uneven forces are applied across/ along the length of the member.

The Cast centre of the salisbury differential where the axle tube enters is a stress/ failure point when load excedes the design strength

JC

while the MD actuator block was the place of failure, is it fair to say it was the cause.

Think about the definition of cause.....

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Originally Posted by steveG

I've heard that the 130's have thicker tubes than 110's. Anyone know the thickness of each one?
Steve

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I have a SIII Sals I cut open and posted the wall thickness on here. From memory it was 5.8 mm.

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Originally Posted by djam1

Maybe some form of brace from side to side could prevent it?

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There are plenty of braces or stiffeners available for Dana 60s (which are basically the same axle). Buying or designing one that won't foul the suspension or fuel tank on a 110 is a bit more of an issue.
e.g. (not endorsing this one, just an example)
https://www.aulro.com/afvb/images/im...13/06/1374.jpg

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Originally Posted by uninformed

while the MD actuator block was the place of failure, is it fair to say it was the cause.

Think about the definition of cause.....

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Caused no, however contributed to may be fair. Every non-MD sals I have seen fail failed where the tube goes into the centre. Every MD-equipped sals has failed at the actuator block (bearing in mind that is only 2 - Red October's 110 and the one on JRTs website).

I recall the MD installation instructions for a sals locker were explicit about making sure the hole in the housing had rounded corners and the actuator block welded on in short runs using a cold weld. Which suggests they were at least aware of the possibility.

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Originally Posted by isuzurover

I have a SIII Sals I cut open and posted the wall thickness on here. From memory it was 5.8 mm.




Caused no, however contributed to may be fair. Every non-MD sals I have seen fail failed where the tube goes into the centre. Every MD-equipped sals has failed at the actuator block (bearing in mind that is only 2 - Red October's 110 and the one on JRTs website).

I recall the MD installation instructions for a sals locker were explicit about making sure the hole in the housing had rounded corners and the actuator block welded on in short runs using a cold weld. Which suggests they were at least aware of the possibility.

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Very true, it is all about the flex/ load cycles at stress raisers, causing crack propagation and then failure :(

jc

apparently the 110's fitted with load levelers were a bit more prone to bending and failure....mind you Id say 99% of all this comes from overloading.

Ben, another thing to have to design the truss around is the A frame mount and ball joint...

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Originally Posted by uninformed

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Ben, another thing to have to design the truss around is the A frame mount and ball joint...

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That is part of the suspension isn't it ;)

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Originally Posted by inside

I haven't had this happen to me but what I have had is a bent axle housing, only slightly but enough neg camber for the axle to touch the inside of the stub axle.

Searching around there seems to have been a few failures where the axle housing has snapped on the long side. For any metal expert people out there can you conclude what the first picture shows as far as metal failure? The failures seem to happen due to very loaded expedition vehicles so I'm thinking it's the weight combined with bad roads.

https://www.aulro.com/afvb/images/im...13/06/1361.jpg

http://aciai.me/i/d5Q3T.jpg

Here's another vehicle. Seems very overloaded.

http://aciai.me/i/qfsLJ.jpg

http://aciai.me/i/iBmna.jpg

http://aciai.me/i/HS39B.jpg

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Looking at the registration (North West Province South Africa) and the vegetation (mopani) I'd say this is somewhere in Southern Africa around the tropic of Capricorn.
A pot-hole would be the culprit.

An axle brace could have helped, but considering the depth of some pot-holes in Africa, maybe not......... :o

Fatigue failure at the stress raiser caused by the abrupt change in stiffness from the thin walled axle tube into the cast housing.

IMHO nothing to do with the plug weld.

IMHO for carrying heavy loads, long distances over rough roads, they should have used a heavier wall thickness for the axle tube.

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Originally Posted by Bush65

Fatigue failure at the stress raiser caused by the abrupt change in stiffness from the thin walled axle tube into the cast housing.

IMHO nothing to do with the plug weld.

IMHO for carrying heavy loads, long distances over rough roads, they should have used a heavier wall thickness for the axle tube.

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In the red 110 it sure looks like the tube has just pulled out of the cast centre, maybe it had not been plug welded.

I have seen Series 3s where a full weld had been added around the joint and would be very wary of that as a solution - more likely to fail because of the weld there.

Bob

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Originally Posted by Bush65

Fatigue failure at the stress raiser caused by the abrupt change in stiffness from the thin walled axle tube into the cast housing.

IMHO nothing to do with the plug weld.

IMHO for carrying heavy loads, long distances over rough roads, they should have used a heavier wall thickness for the axle tube.

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Looking at the photo of the center housing showing the opening where the tube has pulled out, the remainder of the tube is still inside.
To me it doesn't look like it has failed where it enters the housing, but that the crack has initiated from the outboard edge of the plug weld.

Am I missing something?

Steve