Which Locker POLL ?

[fridgie]

Any locker can fail

I believe this particular failure would be lokka only as the air lockers engage differently (happy to be corrected)

[Mattstruck]

So can this happen with any locker or is it just the design of the Lokka ???

No fault I don't think Mooons. Only fault was a faulty install IMHO...

Anything can/will fail if incorrectly Installed. Unless it is unbreakable
Sorry...

[har05l]

So easy to be forgotten, Did you install yourself second time Alco ?

To answer your question salt, no he didn't

He gave the original installers a 2nd go as it was covered under a warranty. He did though get bent over for an additional installation fee but I'm sure if it fails again the workbench in his shed will be getting used to do a rebuild

[coxy47]

So can this happen with any locker or is it just the design of the Lokka ???

Theoretically yes but extremely unlikely as the main shaft and the cross pin aren't removed during the installation of a manual locker as it usually replaces the entire carrier. But there will still be a cross shaft so it is still possible however unlikely that it will happen.

[Mattstruck]

If your looking at "probables" then yes a Locker and a Lokka can both fail.

As we just saw a Lokka failed due to a pin not correctly installed.
A Locker could fail if a bolt was not correctly installed.

Bens sounds like similar install fault so hardly an epidemic of failures.
Maybe due to "one off" installs by people not experienced in their installation.
Lockers on the other hand are installed daily buy ARB. They know how to do it really well and quickly, they know all the tricks.

[Lee-thal]

oK,

So the retaining Pin in the cage you guys are talking about, WAS STILL IN PLACE when we pulled it further apart yesterday,

Trust me cause i had to use a punch and some decent force to get it out,

Anyone that wants to come and have a look and give an opinion i am more than happy for you to do so,

I believe it is a failure of the pin, but without having much to do with these things i cannot be 100% on this.

Cheers Lee

[Mattstruck]

Bugger. How the hell can that, properly installed, break???
I'm confused...

[Lee-thal]

This i think is where it is the unknown Matt,

there should be no way apart from metal fatigue/failure that this should occur, that i can see anyway

[coxy47]

This i think is where it is the unknown Matt,

there should be no way apart from metal fatigue/failure that this should occur, that i can see anyway

Wow I really didn't expect that. Yeah the only way this could occur is fatigue or or outright failure through a manufacturing defect. I did notice in one of the photos the shaft has failed along the centre of the hole for the pin which would have been the first failure. That's that's the point of interest.

Can anyone tell me if the pin through the shaft runs parallel or perpendicular to the ring gear?

[Lee-thal]

come down and have a look at it Chris,

You can see it all then,

[salt36]

So easy to be forgotten, Did you install yourself second time Alco ?

To answer your question salt, no he didn't

He gave the original installers a 2nd go as it was covered under a warranty. He did though get bent over for an additional installation fee but I'm sure if it fails again the workbench in his shed will be getting used to do a rebuild

Ah ok, I wasn't sure....

Not too difficult to fit really, a couple of critical points to check along the way but anyone mechanically minded can do the job.

[salt36]

So can this happen with any locker or is it just the design of the Lokka ???

This can happen with the oem diff if the retaining pin comes out.....

[salt36]

oK,

So the retaining Pin in the cage you guys are talking about, WAS STILL IN PLACE when we pulled it further apart yesterday,

Trust me cause i had to use a punch and some decent force to get it out,

Anyone that wants to come and have a look and give an opinion i am more than happy for you to do so,

I believe it is a failure of the pin, but without having much to do with these things i cannot be 100% on this.

Cheers Lee

Wow the centre pin failed then, that is so unlikely, does anyone know where the Lokka is manufactured ?

Jarad has a good case for warranty, 4wd Systems would want to see it, no doubt....

The stress on the centre pin is mostly across the pin, from the two half round parts of the Lokka, Fridgies photos above show it. I couldn't see the pin failing from that. A half circle pushing through the pin to engage the other half circle.
This happens at both ends of the pin at the same time. There is very little 'pulling' force on the pin.
There would be some 'twisting' force on the pin though and I guess this could be where it broke away from the retaining pin.

Lee was there a piece of the centre pin with the retaining pin hole in it somewhere ? This bit could tell a story. Given it was driven so far I doubt it would be recognisable.

Coxy could have it investigated to find if it was fatigue or crap steel to begin with....

[salt36]

This i think is where it is the unknown Matt,

there should be no way apart from metal fatigue/failure that this should occur, that i can see anyway

Wow I really didn't expect that. Yeah the only way this could occur is fatigue or or outright failure through a manufacturing defect. I did notice in one of the photos the shaft has failed along the centre of the hole for the pin which would have been the first failure. That's that's the point of interest.

Can anyone tell me if the pin through the shaft runs parallel or perpendicular to the ring gear?

Here you go mate, from the manual..... From memory the lock pin is close the end of the centre pin....

Front diff lock pin.JPG

[fridgie]

uploadfromtaptalk1360830134667.jpg

If you look closely at the piece on the right it may be where the pin went through?? Looked too perfect when I was there to be a groove worn into it.

[coxy47]

If you look closely at the piece on the right it may be where the pin went through?? Looked too perfect when I was there to be a groove worn into it.

Yeh mate it is. Looking at the left side of it in the photo appears to be where it failed. I hate to say it but it looks more and more like fatigue related. It also appears to be darker on the failure point from the photo which is another indication of fatigue.

Saying that though it doesn't mean it wasn't due to poor material used for the pin. As this will make fatigue occur more quickly.

For this to fail there in this manner I can't see it happening without an underlying fault. Option 1 being the pin having room to move in the centre from elongation of the holes or a undersized pin which is less likely. Option 2 being a faulty material.

[Mattstruck]

As said, this makes no sense. The force applied to the large pin is a twisting force long ways along the length of the pin. Even a rubbish steel pin should handle it easily.
Come to think of it it really can't be that because the pin has been snapped off across its length. Like cutting a bit off a sausage.
Something has happened to allow the pin to move up and out of its correct position where it's hit the carrier and snapped.
Could something have happened, something had broke, to allow the pin to have play, move out and snap?
From my memory of the install it's shimmed into the carrier? So impossible?

[Lee-thal]

There was a piece of the main pin still locked in by the pin through the cage, the last piece only came out once we had removed the pin,

i think there are 4 large pieces overall but i think 3 out of the 4 were broken once the first piece had failed,

[Homer]

Doesn't make sense to me in these photos...how does the pin "twist/shear" in half with no load in that direction and while contained inside a housing Even a brass pin wouldn't fail in that way in that application...

I'd expect wear/axial shear lines in that situation?

Either that or I'm looking at the pin fitment and forces completely wrong the pins act very similar to a key on a shaft/coupling hub no?

[coxy47]

I'll do up a loading drawing of it this afternoon to show how it would be been loaded.

Lee I won't get to swing past this afternoon due to work but ill try and get there Monday arvo.

[Lee-thal]

Ok Coxy, No worries

[coxy47]

Ok so ive now got the parts of the pin that failed off Lee and f*ck its a decent failure. So everyone is aware it is the pinion shaft that failed i.e. the approx 20mm diameter pin that runs through the lokka.

Based on a close look and ill update photos when i get i chance, it appears to have failed initially due to fatigue at the pinion shaft retaining pin hole. which allowed the pin to move freely in the diff and ultimately cause the other failures. One thing that is interesting is that there appears to be a ductile fracture at the opposite end of the pin which I didn't expect.

I'll see what else i can find out about it from a professional as this definitly isnt my specialty but i doubt it will be much without being able to compare it to another pin that we know is in reasonable condition.

[salt36]

Fatigue

I can't remember how much movement, if any, there was between the pinion shaft and the retaining pin.

Bit of a concern as that will be the weakest point of the shaft.... hopefully it is a one-off failure....

Good on you Coxy

[Mattstruck]

But how could something which doesnt move fatigue???

[fridgie]

But how could something which doesnt move fatigue???

We all ask YOU that after one of your 'workouts'