Broken ARB Piston (1 Viewer)

[alvarorb]

Guys,

CruiserDrew and I took a part my front axle this weekend.
My ARB front locker would engage, but soon it would loose air and would cycle the compressor. Then the locker would disengage until the compressor had generated enough pressure.
In the process a lot of oil would spew out of the ARB solenoid. Meaning that diff oil was traveling up the locker air hose.

This morning I took the 3rd member to River City Differentials and soon after Sean called me to tell me the news.

He told me that the gears are wearing really nice (it's been over 75.000 since I upgraded to 4.88). He replaced all the seals (locker and pignon), plus the o-rings. But was he was ready to complete his job he noticed something odd. He found a broken ARB locker piston.

Has anybody else seen this?

Regards

Alvaro

 

[Atoyot1031]

I haven't heard of that before. Kinda interesting since people are normally saying that the ARB are tougher than the factory elockers (unless it happens to you, then it just sucks).

 

[Shipwreck]

Has anybody else seen this?

Yep.

The broken piston is easily recognized once you remove all of the exploded bits of the housing.

You wheel your truck hard Alvaro. Nothing is bulletproof.

 

[whosthecoolguy]

Holy cow.

 

[alvarorb]

Mine did not break as catastrophic as yours. I could not tell what was wrong other than the locker not working properly.

Alvaro

Yep.

The broken piston is easily recognized once you remove all of the exploded bits of the housing.

You wheel your truck hard Alvaro. Nothing is bulletproof.

 

[CodyRx7]

Oh dear god.

I just finished installing my ARB lockers. Please don't ever post such a thread again...

(runs away screaming)

 

[Shipwreck]

Holy cow.

Oh dear god. ...(runs away screaming)

Don't worry too much guys. This air locker had been in my FJ40 for about 14 years. It had seen a lot of abuse. It was my daily driver as well as weekend wheeler. I run a 2F /sm420 along with a Toybox down to 37" IROKs. That locker saw a lot of torque and a lot of miles. I think I put in around 170,000 miles before it gave up on the way to work one morning.

My point of posting was to demonstrate that even ARB lockers are prone to wear and fatigue.

Alvaro, How did the cross shaft look? Mine had noticable wear and had sheared at one end. I dont know if this is what led to the failure, but now I carry a spare shaft in my parts cache.

 

[alvarorb]

I've not seen the broken piston. I'll post some pics when I get back my 3rd member.

Regards

Alvaro

 

[PKP80]

I do have diff oil get up into airline, but I have not noticed any additional cycling or locking issues. I will have to check once I have the the rig back at home. I haven't heard of such a thing either and would be interested to know what ARB says about it and what (if anything) they intend to do about it. Keep us posted

 

[sleeoffroad]

The piston is the plastic piece that is inside the locker that locks the mechanism. Not sure why it would have broken, but I am sure it was not as bad as the above pictures which pretty much shows the locker case that broke. Possibly due to the cross pin that broke?

http://www.arbusa.com/alac/alsp/Air_Locker_S&P_Manual.pdf is a link to the detailed diagram of all the ARB lockers. You can choose your model number and then get an exploded diagram.

 

[alia176]

Considering what you put La Cabra through, I'm not overly surprised. What does ARB say?

 

[alvarorb]

Ali,

I don't know. Sean said that it was pretty rare to see pistons go like mine.
He ordered the part and we should have it here tomorrow.

I will have pics soon.

Alvaro

 

[Tapage]

Looking forward on it ..

Years ago I was dealing with oil coming out from my solenoid when shut off the locker .. ( rear ) but notice ( months later ) that my axle breather was bloked, that I thought was the reason that the hot oil goes into the locker ( as when the oil get hotter expand .. )

Solve the breather issue and no more oil in the solenoid ..

 

[alvarorb]

Here's a picture of my broken ARB locker piston. Sean at River City Diffs does not know what makes them break. He did say, that it's rare but more common now than before.

The plastic was broken every 90 degrees. It's a good thing I he noticed the broken piston before sending me home with the rebuilt locker.

Regards

Alvaro