ARB Air Locker Install

Article and photos courtesy of Chuong Nguyen, AKA Boss

Last Tellico trip I attended, I quickly found out that having a Detroit in the back and Open up front is not the right combo if you want to get up some tougher trails there. I found myself winching up some areas where some people that were locked at both ends made it through. A friend there asked me "What's your next mod before you come back and tackle these trails again?..." "A Front Locker" I replied with no hesitation!
With a Dana 60 front axle, I had a few options as far as a "Locker". I didn't want a Limited Slip differential.
Some examples are: Detroit, "Lincoln", Spool, and the ARB (at this time, the OX for the D60 was not available yet and neither was the E-locker from Eaton). I wanted to go with the ARB, since it allowed me to switch the locker on to Full lock when needed and Open when not (This will help alleviate some of the strain on the front-end components when your axle isn't at full lock when it's not needed). I asked around to some people that have used it and abused it and most of the feedbacks I received were positive. Sounds like this locker is only as good as the axle it's going in, and with the D60 front axle, that's pretty much as good as it gets for the front  (for now anyway ).

The ARB was also the priciest of all the options, it also requires an air source to operate it as well. I decided to purchase the ARB’s Air Compressor for simplicity sake. I don't intend to use this puny A/C to air up my tires or anything, so I think it will have a long and healthy life, you can use any other outside air source to operate it though, even CO2.

I was almost set on having a pro do the installations for me, but I couldn't stand the thought that some other dude is working on my truck, plus the fact that around here, they charge an arm and a leg to put it in. It's not as simple as a Detroit or Spool or any other locker to put in because of its "selectable" option. I consider myself an "average" DIY (Do it Yourselfer), maybe more at the bottom end of that, and was told by many that I should not attempt this. After thoroughly reading through the detailed instructions that came with the ARB, and doing some research, I decided to tackle this job.

This article is intended for the Dana 60 install, but any other GM front axle is pretty similar to this.

Tools “I” used:
*assortment of sockets, wrenches/ratchets
*dial caliper
*dial indicator and magnetic mount
*drill
*drill bit (7/16th”)
*tap-1/4" NPT
*hub socket to remove lock nuts on D60
*torque wrench
*impact wrench (makes some jobs easier/faster)
*oven (for heating up the ring gear)
*press
*wire crimping tool
*crowbar (for removing the carrier, and ARB)
*brass punches
*2 jaw puller (3 jaw would've been better) (to remove the bearings)
*die grinder (to hollow out the old bearings for easy removal while checking the backlash, before pressing on the new bearings)
*razor knife, (for cutting the air hose)

Things I recommend you get before you do this:

*New shim pack for the passenger side (the ARB kit comes with shims for the driver side) I didn't get new shims (forgot), so I reused my old ones...they were still in good condition.
*LocTight #272 (red), #567 (Thread sealant compound), and Teflon Paste
*New bearing for the passenger side (you'll most likely destroy the old bearings if you remove it the way I did)
*Hi Temp grease
*3/8th fuel hose (about 7ft) (I put the ARB blue hose into the fuel hose to protect it from heat and other elements...I think this will work great for protecting the blue hose...you'll still need to watch where you're routing it though)
*zip ties
*You'll also need to fab up something for the switch mounts...I used thin wood and used a cut-out tool to cut out the rectangle hole for the switches)
*Several Bottles of Brake Cleaner
*gear oil – whatever brand the parts store carriers (80W/90W) – change often.

Installation:

Park the truck in the driveway and chock the rear wheels. Disconnect the batteries

Drain the Diff and remove the axle shafts. I won't go into details on how to do this, b/c if you don't know, then I don't recommend you do this install.

Once it’s done, remove the cover and you’re now looking at the stock carrier/ring gear assembly.

Now check the backlash with a dial caliper on a magnetic mount. Record your reading, spin the pinion yoke about 90 degrees and recheck, now get an average.

Next, I marked the bearing caps to which one is passenger side and driver side, and to which way it bolts in (up or down). DON'T MIX THESE UP. The bearing caps are made specifically to their respective sides.

You can now remove the bearing caps, I used an impact wrench. Now, with the axles out, remove the stock carrier, I used a crow bar to remove the carrier. A little nudge and it will come out, be careful, not to drop it, it's heavy, especially while you’re lying down on the ground under the truck.

I then cleaned the entire insides with brake cleaner. Now, place a cloth around the pinion and insides to prepare for the drilling. The spot you choose to drill the hole is not too crucial, but it should be someplace where it won’t cause the copper hose to come in contact with the ring gear.

The drill I have is long, so I couldn't drill the hole from the outside. Instead, I drilled it from the inside. Use a 7/16th-drill bit.

After that is done, now you have to tap the hole, use a 1/4" NPT tap with lots of cutting oil.

Now, back to the carrier you just removed.

Remove the bearings and mark which ones are which side (not really too important if you bought a new one for the passenger side.) I used a bearing puller to get under the bearing and then a 2-jaw puller to pull it out. I dropped a large socked in the hole for the puller to press on. Note: You will damage the bearing with this method. That is why I recommend you get a new set of bearings for the Passenger side, be careful not to damage the shims if you intend to re-use them. If you were smart (unlike me) and bought a set of new ones for the passenger side, then you won't have to worry about it. (I had to reuse some of the old shims b/c I did not get new ones...however mine were still in good condition...I don't recommend you re-use shims that are in bad condition.

I then honed the inside of the bearing, with a die grinder, so it can slide in and out of the locker with ease. (this is to make light work of testing how thick of shims you need).

Now, remove the ring gear bolts on the carrier. I used an impact on it.

Time to press on the Driver side bearing, I used my 12 ton press to press on the new bearing. Do not place any shims in-between the bearing and the locker, They can be pressed on first, since you won't be shimming this bearing. I used a small exhaust pipe (2.5" ID) and plate to press it on.

Now put the ring on the ARB locker, I had to heat the ring to 210 degrees in the oven to get it to expand and fit over.

what's for dinner honey?...."A nice smelly Ring gear", Your Kitchen will smell like gear oil when you open up the oven. Now, put lock tight 272 on the ring gear bolts and torque them down to 100 lbs in a crisscross formation (like wheel lugs). Make sure the threads are cleaned on the bolt and in the ring gear and use lots of brake cleaner and compressed air to blow it out.

Now its time to take a lot of measurements and use some basic mathematics skills to get a rough estimate on how thick of the shims you need to put on the passenger side. You’ll need a dial caliper or a micrometer. This is explained in detail in the ARB manual.

Now, put in the shim(s) needed and put on the honed out bearing (it should be able to slide in and out with some ease). Place the seal housing over the grooved end (do not put the O-rings on at this time, since you may damage them), and put the Master Shim provided by ARB on the other side.

Now, put the ARB in the diff housing and bolt on the Bearing cap for the passenger side, make sure you put the cap in the exact side up.

Now, move the locker all the way to the left, and measure the space between the Master shim and the housing and add the carrier bearing pre-load amount to that and this is the shim thickness needed on the driver side.

Now carefully position the copper line to where the hole you drilled. Your hands are the best tools for this job. Cut off the remaining line not needed with a brake line cutting tool. Leave about 1" of the line sticking out of the hole.

Now, take some measurements on where the copper line is and that is where you will make the notch on your driver side bearing cap, I used a cutting tool to make the notch...quick and easy.

Remove the entire ARB locker assembly and press on the passenger side bearing, make sure the appropriate thickness shims is in there first. Press the bearing firmly against the shim. Now, put some diff oil on the 2 O-rings supplied by ARB and stretch them over the grooves...do not roll them on since it may damage them.

Apply a little diff oil on the bearings as well, place the seal housing over the O-rings in a twisting motion, this should seal it up. Place the appropriate thickness shims in-between the seal housing and the master shim.

Now, put the ARB locker in the housing again...this will take some pushing and persuasion to get it in. I didn't have a diff spreader, so I used a brass punch and hammer to help "persuade" it in there. DO NOT bang on the locker or anything with a hard face hammer, such as a sledge, you could damage it.
Bolt on the passenger side bearing cap first and then line up the copper line with the driver side notched bearing and bolt that on. Torque the bearing caps down to 80lbs. Recheck the Backlash...make sure it's within the spec.

Route the copper line to the hole and bend it out of harms way.

Time for the Bulkhead fitting work: Now put the inner compression nut fitting and the 3/16th ferrule over the line. Leave about 5mm of line sticking out of the ferrule.

Then bolt down the bulkhead body over it.

While supporting the inner nut, tighten down the center compression nut (make sure you used the side that has the relieved thread). When tighten, this should clamp the ferule down on the line. Now loosen the center nut one full turn, so that the bulkhead body can spin freely on the line.

Apply thread sealant to the bulkhead body fitting and tighten it down in the hole you tapped.

Time for the blue hose.

First put the spring on, (small diameter end first), then the outer compression nut, then the ferule (5mm) and then put the support tube in hose.

Stick the hose all the way into the center nut fitting and screw on the outer nut.

This is how it all should look when you're done:

Route the hose away from the exhaust and other heated objects and things that can potentially tear or melt the hose. Make sure you leave some hose room for "flexing" purposes. Cut it to length, I used a 3/8th rubber fuel hose to protect the blue hose, you can now take the supplied zip ties and tie it in place.

Time to mount the switch and the ARB A/C, here is where I mounted mine.

Connect all the wires to it's appropriated wires. I won't go into detail doing this...it's very simple. Just make sure you put Teflon paste where required. Connect the blue hose into the push in fitting. Make sure the hose goes all the way in there.

Now, reassemble your axles and brakes.

Reconnect the battery and turn on the A/C switch, it should only be on for a few seconds. Before you switch on the locker switch, lock the front hubs and spin one side, the opposite hub should spin the other way. Now, turn the switch on for the locker, both sides should turn the same way. Check for leaks with some soap in water in a spray bottle. The ARB A/C should not turn on again for at least 15 minutes (according to the instructions), mine never came back on after an hour or so of testing, I have no leaks!! Put the cover back on and put some oil in there (80W/90W) and you're done!!!!

Testing:

A friend and I went in the woods for a little testing, I noticed that with the front locker engaged, it cut down my turning radius a little, that’s because both front tires are now locked, so the tires spin at the same time, same rate, no matter what. It’s good to know that I have the option of turning it off when I don’t need it.
Steering with the front locker engaged was not hard to do, it was the same as if the front-end was open (but keep in mind, I do have the hydro assist steering setup). The truck now will climb and pull through terrain it never could before, there is no question in mind that this is one of the best mods I’ve done to my truck!

NOTE: After close to a year of abusing this thing, it's held up quite well, gave me no problems in the diff. I once thought I had a bad O-ring problem in there because the compressor kept running every 10 seconds or so, but I found out that the compressor itself was leaking air, some RTV sealed that up and now it's back to the way it was. Definitely thumbs up to my install job!