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so how difficult is it to tear the rear-end apart and get it back to gether right withought messing up the alignment of the ring & pinion?

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You didn't say anything about what it is doing wrong, or what rearend you have or or ...

...so there is gonna be a lot of guess work here.

There really isn't much inside an ARB. They are elegant in their simplicity. A lot like an open diff, with the addition of a cage and lockiing ring to lock the spiders to the carrier and a pressure ring to operate it all.

I am going to make some assumptions here.

1) That it does not engage the locker.

2) That you have an AMC 20 rear end.

I am going out on a limb and guess it was either run on low air pressure or a couple springs broke and broke some teeth on the locking ring.

The good news is - ARB is very good about having replacement parts for the internals. And they will sell repair parts direct.

Also ARB has their manual online.
Here is the one for an AMC 20 3.08 and up.

http://www.arb.com.au/alac/alsp/2-RD60.pdf


As far as getting it apart and back together.

I am going to make a couple more assumptions.

1) You have a decent assortment of hand tools
2) You have good basic mechanical skills.
3) You just have to pull the existing carrier and repair it and reinstall.


If so - As long as you are very careful and keep track of all the shims to make sure they get back where they came from, you should be fine. The relationship between the ring and pinion doesn't change just because you took it apart.

If you have to get a new carrier (the housing) then all bets are off. You will need to set the gears up again, just like it was all new parts. And at that point, you may as well put in a bearing/ mstr install kit.

Special tools wise, the only thing I can think of off hand, is the locking bolts that hold the carrier halves together. It sticks in my head they they are a funky size - like 6 MM 12 point and you will want a good quality wrench to break them loose if they have never been apart.

While you have it apart, replace the o-rings on the acuator end. When you order the o-rings. Order 2 sets. It is easy to pinch one reinstalling the seal housing and you don't want to wait another week for new o-rings.
(Ask me how I know this and why we stock ARB o-rings now)
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And be VERY CAREFUL with the copper tube running from the air ring. (ARB calls it the "seal housing") they are easy to crack.

Last item. When you find out what broke. Try to play dectective and decide WHY. Maybe it just broke, but more likely there was some other problem. Air pressure. Contaminated fluid. Low or improper fluid.

You don't want to do this again because you didn't fix the original problem.

Other than that - use your head, take your time and with a decent shop manual for the rear you are working on, you should be fine.

Good luck,

yes you are right it is an AMC model 20 Rear-end. when the rear is locked (the hubs, or air locker it doesnt matter). it works ok, so it seems (when just going straight). like a full locked rear-end. but otherwise it does not work like a slipping rear-end. like when I try to turn, one wheel locks up and the other kinda drags. if I give it some gas it makes a loud clicking noise. (which I know isnt right) also when I unlock the rear end there is nothing it is like it is in nutrel. but in 4wd High it drives great in fwd. but I dont like doing that. how many jeeps do you know of are front wheel drive? well Ill check out what you said and give updates thank you very much. if there is anything else you or anyone else might be able to help with please let me know.

Thank you very much
Marc

DOn't know much about arb's but pulling the carriere is easy. Pull the axle shafts. Cover off, then (5/8" socket might be 3/4 can't remember) and take the cap bolts out. make sure you mark or know which direction the caps are on the housing as they must go back on the same way. Once caps are off either feed a rag into the ring gear till it pushes the ring out of the caps or lightly use a pry bar to "pop" it out of the housing.

Are you sure you have an ARB?
To be sure, there will be an airline comming off the top of the diff somewhere...inside, there is a copper tube going from that line to the right side of the carrier...this is what activates the piston and locks the diff. Without air, springs push it apart and you have an open diff.

Look at the lower pic...specifically, the 10 oclock pos of the diff...


The blue thin blue hose is the air line for my ARB. If you don't have something like this, you don't have an ARB.....

Can you take a pic?

yes I have an ARB I can take a pic to be sure but I do have the hoses and the copper pipe. Ill try to get a pic today

How are you locking and unlocking the rear end? Did the jeep include an air compressor?

If the rear end stays locked even with the air off (you might try disconnecting the air line to be sure), then you have a problem. ARB's are very quiet....one of the reasons they are popular....no clicking, clacking, clunking...just locked or unlocked....the only click you 'might' hear is when you first energize the locker....but after that...quiet.

yes it has an ARB air compressor on it and wether that is on or not the rear is locked in. I was locking the hubs just like the front end on most 4 wheel drives it has them on the rear also. I still havent gotten pics yet Ill get them soon I just got it into the garage a little while ago.

Don't really need pics now....you have a problem...As noted above, ARB's don't make noise......however, not all is lost.

First, assuming it's installed properly, it takes very little volume to lock...just pressure...I belive it's around 80 PSI +. If the locker is plumbed straight to the air tank without the solenoid...then it will take a long time for the air pressure to bleed down enough before it unlocks.

Other issue...noise...since it appears that you are quite good now at pulling the pumpkin cover...pull it off....jack up the rear end and turn it. If you hear noise comming from the center...you have problems....

The good news is that as pointed out above, parts are available...depending on what is wrong, in most cases, you can remove and replace without major work...you pull the axles out a little...remove the carrier bolts...and pull the ARB (after you disconnect the coper line). Keep track of what shims whent where....fix the problem, put it back (using the same shims) and your done.

Good Luck

well here are some pics of it.

Yep....that's and ARB.

Good looking rig...is it smog legal?

Can you pinpoint the exact location of the sound?