[Daless2]

How-To Convert an Ox Locker to Air Operations

This write-up will be posted here in sections as I find the time to do them. Please bare with me it will not take all that long.


Preface

About 18 months ago I began designing and building various ways of shifting an Ox Locker without the Ox Shifter and Cable.

Why?

Well to be honest it wasn’t because I have ever experienced any problems with the shifter or cable, but rather more then a few other folks had, and in truth I am not nuts about the cable design myself.

I built three different shifting systems, one air powered, one electric and one hydraulically powered.

All worked, but as my friend Blaine so kindly points out to me I have a tendency to sometimes make things more complex then they need to be. (Everyone needs someone to keep him or her honest and simple. Thanks Blaine.)

This write-up is not about my designs to convert an Ox Locker to be Air Operated, but rather will, for the most part describe a super simple system developed by a young man named John Lemieux.

Blaine put me in touch with John. He owns a shop in Corona, CA called All Four Wheel Drive.

John is a world-class gear man and was already working on a conversion design to eliminate the Ox Cable and Shifter Assembly. After talking with John and receiving a very generous amount of his time, both over the phone and during a visit to his shop in Corona I scraped my designs and adopted his.

To date, John has been running his D30/D44 and I, my D35 Ox locker, for more then a year using this design without any failures, popping ,or breakage of any kind.

Please clearly understand; while I am documenting this How-To-Do-It, full credit belongs to John Lemieux.

I believe John is being very generous, considering he makes his living doing this kind of stuff, in allowing me to put this information out into the public domain on this forum. For this reason I feel justified in plugging his shop with his contact information. I hope he doesn’t mind. I don’t think most folks here will mind either.

John Lemieux
All Four Wheel Drive
21765 Temeseal Canyon Rd
Corona, CA
(909) 277-1037
all4wd1@aol.com

Thanks John.



Air Ox Conversion Overview

Here is a picture and a brief over view of my Super 35 Ox Locker converted to air operations..




There are only TWO (2) Main “Operating Parts” to be added to the Ox Locker to convert it to air operations, an air cylinder outside the cover and an Allen Cap Bolt threaded into the Ox Shift Fork.

In the above picture, sticking out of the Ox Cover is a simple air cylinder.

Notice there are two airlines. The line on the right is the air pressure line. It goes to my ARB Compressor. (It also goes to my York Compressor as a back up system. I like redundancies.)

The line on the left is just a vent hose. I have it running up along side the differential vent hose.

Both lines are actually nylon (hardline) air hose covered in 3/8-inch fuel line hose for protection. (I don’t know if this is needed or not but it makes me feel better.)

The air cylinder is made by SpeedAir and is available from Grainger for $17.85 The part number is 6W073. (See complete parts list later in this document.)
The interchange chart says that the Bimba air cylinder # 091-D is an exact replacement air cylinder if you can’t get the SpeedAir unit.

This air cylinder is a double acting cylinder with 1-inch stroke, yet only the “push out” side is being used in this design.

The cylinder is nose mounted via a 5/8” x 18-tpi threads to the OX Locker cover. (Folks it simply screws right in!)

A stainless steel piston having 5/16 –24 thread extends from the air cylinder when air pressure is applied. The threads on this piston are not used. Rather the end of the cylinder piston simply pushes against a Stainless Steel (hardened) Allen Cap Bolt which threads into the Ox Shift Fork.

That’s basically it folks. That’s the meat.


It takes a minimum of 48 PSI of air pressure to operate and lock the OX reliably without any popping. I have tested this extensively to see how low the pressure could be taken.

My current ARB in the front is set for 85 PSI. So I have that same pressure going to the Air Operated OX Locker now.

For the size air cylinder used in this design, 1 PSI of air pressure into the cylinder will result in 0.89 Pounds of Pressure available at the air cylinder piston.

So at 85-PSI air in I have 75.6 Pounds of pressure holding the OX Locker in the locked position.

When the air pressure is released from the Air Cylinder the Ox Locker (Cam Springs) push the cylinder back out, much the same way they do with the new shifter assembly.

The vent hose (left hose in the above picture) enables this to happen without any pressure build-up to be overcome.


Here is a picture of all that goes inside the Ox Cover.




On top I am showing a hardened Allen Cap Bolt that you can buy at any hardware store.

On the bottom you can see what this Allen Cap Bolt look likes when installed in the shift fork of the Ox Locker. (Please note; there is no need to take the Shift Fork out of the cover to install this Allen Cap Bolt. I am only showing it here for clarity.)

I have found these Allen Cap Bolts at Ace Hardware in both Hardened (black in color) and Stainless Steel (shiny in color) for $0.53 each.

The Allen Cap Bolt is ¼” in diameter, Two (2) inches long, and has 28 treads per inch.

Here is a drawing of the exact measurements taken by micrometer of the Allen Cap Bolt I have used.




If you use the air cylinder I used (SpeedAir) and this Allen Cap Bolt in the Ox Shift Fork you end up with 0.200 Inches (200 hundred thousands of an inch) between the end of the air cylinder piston at rest and the top of the Allen Cap Head.



Installation Instructions

Air Cylinder


* Remove the Ox Shifter and Cable from the Ox Locker.

* Remove the Ox Locker Differential Cover

* Clean the inside of Cover and inside the Shift Fork Slider. (The part that the inner cable threaded into.) I use a can of Brake Part Cleaner and some compressed air.

*Put two drops of Medium strength Loc-Tite on the 2”x ¼” Allen Cap Screw Threads.

*Thread the Allen Cap Screw into the shift fork slider from the hole where the cable would normally screw. (Hold the Shift Fork Slider to keep it from turning. Do not over tighten, about 10 ft/lbs is fine.) Let the Loc-Tite set up. (In other words, when looking at the back, outside, of the Ox differential cover, thread the Cap Bolt into the shift fork slider from the right, through the hole in the cover where the Ox Cable would normally thread into.)

* Installing the air cylinder is a straight screw in operation. I did however add a few thin washers to allow for indexing the location of the air fittings on the cylinder. I wanted the side fitting pointed up when the cylinder was tight..

Here is a picture of the air cylinder and the indexing washers I used.



These washers are available from Ace Hardware for $0.10 each. They are copper and made for faucet packing, which means they deform and crush nicely which will allow you to index the air cylinder exactly where you want the side air fitting to live.

The air cylinder should be tightened down to only 10 ft/lbs.

While the Ox Cover is off, now would be a good time to install the two air fitting onto the air cylinder. (See parts list for details on the fittings.) All fitting are 1/8” NPT threads, and are of the “quick connect/disconnect” type. I used a 90-degree elbow fitting on the end air pressure line and a straight fitting for the unused side port.


*Reinstall your Ox Cover. Your now done with the changes to the Ox Locker. Make sure the Shift Fork in the cover engages the Ox Locker Collar on the differential.

That’s it for any Ox Locker changes folks.

All that is left to do now is to install some airlines and provide a means to turn on and off air pressure.


[b[Part List[/b]

Please note, all the parts you need to convert the Ox Locker to air have been documented and described above.

Here is a complete list, including those parts and sources, as well as other parts that I will discuss shortly that you may or may not need to complete a total system for your Jeep.




More to Come

I will be putting up additional instructions of the air lines, air control valve solenoid I used and instructions on how to convert the Ox Locker Shifter assembly into an electrical switch that can be used to send and remove air pressure to your newly converted Air Ox Locker.

These will be put up shortly.

Have a great night, and a Great 4th of July!

Frank

[Jim B]

Frank,

This is an excellent mod.

Thank you for all the work and detail that you have provided. Please keep the rest of the write up coming. I just briefly looked at it and I'm sure I'll have some questions.

My boss is calling me and I need to get of this computer before I get in trouble.

[Daless2]

Last night I covered the two minor parts that you would need to installon the Ox Locker to allow it to be Air Activated.

Now I will give you some thoughts on how to manage the air pressure to activate the Ox Locker.




Air Valve Solenoid

I have found a source for air solenoid / valves, similar in function and spec to the ARB solenoid / valve.

These are made by Mac Value and cost me only $18.95 each, were as the ARB units cost me $52 each. I purchased mine from a local industrial supply house, but with the part number in the table I gave you yesterday you shouldn’t have any difficulty getting this.

Here’s a picture.




The Air Valve Solenoid has three 1/8-inch NTP Ports that are labeled 1, 2, and 3. These ports are connected and labeled as follows.

-Port #1 goes to your compressed air system.
-Port #2 goes to the Air Cylinder on your Ox Locker.
-Port #3 is the Exhaust Port. I have attached a 10” section of air tube to this. That is all you need here.


*Plumb Port #1 (On the right side in the above picture) to your Air System. The threads on the solenoid are Female 1/8” NTP. Sorry I have no idea what your Air System is using. You should be able to pick up a T-fitting at Ace Hardware or Lowes/Home Depot for about $3 to connect right up to this.

*Once you have the solenoid/valve plumbed to your air system you’re all set to install the Air Lines.


Air Tubing Air Valve to Air Cylinder

All the Air Tubing and Fitting meet D.O.T. specification. This is ¼-inch O.D. Nylon line if you use what I used in the parts list this is the same type as used for large truck air brakes. (Read that, they don’t fail easily!)

Running and installing the air-lines really is a simple process. The only think to keep in mind is to cut the air tubing nice and square and make sure there are no burs on the end. (Use a razor knife, not a wire cutter.)

I would order 25 feet of this air tubing, but you might be able to get by with less. The Air Tubing connects to the Instant Fittings simply by pressing the Air Tune into the Fitting. Just push it all the way in and then pull it out and it will seat.

If you ever want to disconnect the air tube from the fitting all you need to do is press the brass collar around the end of the fitting IN and the tube will pull right out.

This is by far the simplest and most reliable system out there.

*I am assuming your compressed air system is under your hood. Start routing the air tubing from there, down along the driver side frame of your Jeep till you get it to the differential.

*Push the end of the air tube into the ELBOW fitting in the end of the air cylinder.

*Note: I covered my air hose with a piece of 3/8” fuel line hose where it is exposed down by the Differential. I’m not sure this is needed, but it made me feel better.

*Working from the rear forward you need to tie the air tubing up and out of the way. I followed the brake line from the axle to the frame, and then the frame rail forward to the front of my Jeep.

*Keep it away fro heat as much as possible, though it can withstand 240 F. Make sure you leave enough slack in the back to allow for articulation. I tied the air tube up to the driver side frame along the fuel line.

*Then I came up the firewall near the Brake Master Cylinder.

*Cut the tube to length to reach the Air Valve Solenoid. (Don’t make it too short. I left some slack.

*Then simply press the end of this tube into the ELBOW fitting on Port #2 on the Air Valve Solenoid.



Air Tubing - Air Cylinder Exhaust


*You want to attach a 4 or 5-foot length of air tube from the straight fitting on the air cylinder (straight fitting).

*Run this length of tubing next to the differential vent hose on your Jeep. Get the end up there, near the fuel filler neck.

*This length of hose allows air to enter the front of the Air Cylinder when you “Disengage” the Air/Ox Locker.

*Tie it up in place with some cable ties.


Air Tubing - Air Valve/Solenoid Exhaust

Install a 10-inch piece of air tubing to the fitting in Port #3 on the air valve. That’s all you need if the Air Valve/Solenoid is installed under the hood on your air system.

This exhaust tube allows compressed air in the Air Cylinder to flow back to the Air Valve and exhaust when you disengaged the Air/Ox Locker.



That’s it for tonight folks. I am out of energy and time today.

The next section I will write in a few days will deal with wiring and converting the Ox Shifter Assembly to function as an electrical switch.

Have a great evening,

Frank

[Daless2]

Jim B, on Jul 4 2003, 08:29 PM, said:

Frank,

This is an excellent mod. 

Thank you for all the work and detail that you have provided.  Please keep the rest of the write up coming.  I just briefly looked at it and I'm sure I'll have some questions.

Hi Jim, over the next week or so I will finish documenting this as time allows.

Not sure there is any great audiance for this info but the handful of folks who have Ox lockers hopefully may find it of some value.

Hope you had a Great Fourth of July,

Frank

PS; Do you have Ox Lockers Jim?

[Jim B]

Daless2, on Jul 5 2003, 12:56 AM, said:

PS; Do you have Ox Lockers Jim?

Frank,

Almost 3 years ago when I put in my D60s, Ox was only making D30, 35 and just coming out with the D44s, I think.

Hence my Arbs front and rear. I'm having a bit of a problem with my front Arb. The center Uring inside the carrier does not seem to be holding and the compressor just keeps cycling. I must have got water on the diff from one of my trips to Tellico and dumb me forgot to check fluids and developed rusty oil.

I changed this oil around Feb of this year, everything was working ok until I tested the locker a few weeks ago. Drained the oil and it had a brown color to it, no water.

The only thing I can figure is that some old contaminated (or grime) oil on the pig's top chamber must have been left (I don't remember blowing it out when I changed the oil in Feb). The diff has a top chamber that you fill with oil to lubricate the pinion, you fill this chamber until it runs out the bottom fill hole, there is really no way to drain it and the only thing I can figure is to blow air out the top.

Obviously something must have worked it's way in, the funny thing is that after I drained the oil two days ago, have left the front diff without oil, ran the 4th of July parade, came back, put the TJ on jacks removing tires. I said to myself, let me try and see if the locker is holding air before I remove the axles, sure enough it is working perfectly again.

I'm now debating whether to go through all the hassle of changing everything or put back oil in it. Might be playing Russian Roulette if I don't brake it open. Decisions, decitions.

[Daless2]

Wiring

OK, so far we have gone through the minor changes you need to make at the Ox Locker Differential, and given direction on how to hook up the air lines to both the Ox Locker Air Cylinder and the Mac Valve Solenoid / Valve.

Here I will cover the wiring and how you can switch the air supply on and off to lock and un-lock the Air Operated Ox Locker.

There is a simple way to do this, and a right way to do this.

First the simple way;

There are two black wires coming out of the Mac Valve Solenoid. One of these wires needs to have +12 volts applied to it and the other wire needs to be connected to ground, through a switch.

When the switch is “Closed” (turned on), the Mac Valve Solenoid will send compressed air from your air system to the air cylinder on your Ox Locker and cause it to Lock.

When the switch is “Opened” (turned off) the Mac Valve Solenoid will release and air pressure will be “Released from the Air Cylinder, unlocking your OX Locker.

Here is a simple drawing on how this can be done.




If you choose to do it this way be sure that the On/Off switch you use inside your Jeep can handle at least 5 amps of current draw. The Mac Valve will pull 3.6 amps at start up, but needs less then 1 amp to remain activated.

*Connect +12 volts through a 10 amp fuse and fuse holder to one of the black wires on the Mac Valve Solenoid.

*Connect the other black wire on the Mac Valve Solenoid to the Switch of your choice inside your Jeep. (This is your Lock and Unlock the Air Ox Switch).

*Connect the second In-cab Switch terminal to your Jeep’s Ground.


Here is a picture of an aircraft type safety switch available at AutoZone for around $10. I believe Brad Kilby sell a “real” version of this switch for a few more dollars.

In reality any good $3 toggle switch will do.






The better way, or in my opinion, the correct way to wire this thing up is through a relay.

This method is a requirement if you choose to follow my direction on how to convert the Old Ox Shifter Assembly into an electrical switch.

This one isn’t rocket science either.






*Connect up +12 volts through a 10 amp fuse and fuse holder to Pin Number 30 on a standard Bosch type automotive relay.

*Connect a jumper from pin 30 to pin 86 on the relay.

*Connect Relay pin 87 to one of the two black wires on the Mac Valve Solenoid.

*Connect the other Black wire on the Mac Valve to the Jeep Ground.

*Connect a wire from Relay Pin 85 to your in-cab switch.

*Connect the other side of the In-Cab switch to the Jeeps Ground.

Using this method will isolate the Mac Valve from the activation switch. As I stated before, if you want to convert your old Ox Shifter to be an electrical switch then YOU MUST use this means to wire things up. The reasons for this requirement is that the reed switch I used in converting the Ox Shifter can only handle 0.5 amps of current.




Converting the Ox Shifter
When I had to come up with a means of switching the Mac Valve Solenoid and Air cylinder on and off I took a look at the old Ox Shifter.

Being I had several of the old Ox Shifter Assemblies I decide to use them.

I converted two of them to be electric switches to control the air solenoids; One for the rear OX Locker and the other to control my front ARB.

Here a picture of how I installed this in my Jeep in my new custom mounting plate.





The shifter on the left (top in picture) controls my front ARB Locker; the one on the right (bottom) controls the rear OX Locker.

There is a small waterproof switch in front of these shifters. This is a three-way switch, on/off/on.

On to the right controls the ARB compressor and air solenoids, on the left controls my York OBA system and back up solenoids. Everything is 100% redundant from the drivers seat, accept for the airlines to the lockers, and obviously what is attached to the lockers.



I have two flavors of this; both are non-destructive to the Ox Shifter Assembly.

Here is a picture of the first system I built.





Here is a picture of the Radio Shack Switch in detail.




At this moment I do not have the part number for this switch in front of me, but I will find it. This switch is sold at Radio Shack in their Home Security section. It is normally used in a Door Jam to arm and disarm an alarm system. When the door is open, the system triggers, when it is closed it resets.


To convert the Ox Sifter you need to remove the Brass Swivel Fitting that the Cable would normally thread into.

*To remove this swivel fitting without destroying the Ox Shifter simply drive out the “roll pin” in the side of the shifter assemble that holds the Swivel fitting in place.

*After removing the roll pin and taking the swivel fitting off, go down to Radio Shack and bought a momentary run push button switch for $2.99 that fit the swivel fitting lock boltholes perfectly. Part Number +(TO BE ADDED LATER)

*Attach the momentary run switch to the back of the Ox Shifter where the Swivel fitting once lived. Hold the switch in place with the two screws that came with the Ox Shifter to lock the swivel fitting in place.

When you move the Ox Shifter into the locked position it will “Make” or close this switch, which then will activate the Mac Valve air solenoid.


Flavor 2

I changed the above design because I wanted to have a waterproof switch inside the Ox Shifter assembly.

I went back to Radio Shack and bought a Magnetic Reed switch used in home alarm systems. (Picture and part number to be posted later.)

The package comes with a small Reed Switch that is encapsulated inside a ¼ plastic tube. I mounted this inside the hole where the swivel fitting lived and held it in place with silicone RTV.

The second part of this switch is a small ¼-inch magnet. I slid it into the shifter where the cross pin used to live and held it in place with silicone RTV as well.

That’s it. 100% waterproof and effective. Plus I was able to utilize the Ox Shifter Assemblies.

I will try to get some pictures up on the parts used to do this. It really was quite simple once I figured it out the first time.

Later I will do a small section on Trail Repair Parts that I carry and show the “Armor”: that can rather simply be put in place to protect the Air Cylinder attached to the Ox Locker Cover.

Have a great day folks.

Frank

[Jim B]

Frank,

After reading slow to digest all of this detailed information the only question I really had, had to do with your last sentence. The armor to protect the air cylinder on the diff from a good wack.

There is someone working to make the Oxs' electric (sort of like the Rubi addition), who knows when they are going to finish but it would be another nice option to have.

Personally I've seen the new cable shifters and they seem to engage/disengage with no effort unlike the first ones they had where pressure was needed. They've also redesigned the inner switches so there is no need to adjust at the diff any longer from what I was told.

There are two things I don't like about them. The switches are huge but I don't think you can get them any smaller to work with cable operation. The second is the cable is a bit stiff to route but in the end seems to be workable. Out of all 3, I personally like the cable engagement due to the simplicity and less things to go wrong. The good thing is that there is another option available.

Have you wheeled with it yet, any quirks? Btw, Ox is very much alive, you can get parts and purchase anything Ox makes through 4 Wheel Parts.

[Daless2]

Hi Folks,

Here is the last short piece of this write-up. My apologies for having taken so long to get to this.


Trail Repair Parts

I carry an air hose coupler and a one-way air cylinder with fitting already installed for trail repairs.

Here’s a picture.




The hose coupler is very simple to use. Should I ever get a hole in an air hose I would simply cut the hose in half at the hole and then push the ends into the coupler and be on my way.

The air-cylinder is different then the one I have installed on my Ox Locker on a daily basis. This trail repair cylinder has only one air fitting which goes to the compressed air line. There is no exhaust fitting. Instead of the exhaust fitting there is simply an exhaust “hole” in the side of the cylinder.

I’m not convinced I would use this on a daily basis because of the exhaust hole set-up. There is just too much “stuff” that can get in there over time. But for a trail repair I don’t mind.

I use this type for a trail repair because of the speed in which it can be installed.

Without the exhaust air fitting all you need do is remove the broken air cylinder and screw this one in. Connect the single air hose and you’re on your way again, holding no one up for more then a few minutes.

I have tested this and can honestly tell you I can do this swap in less then two minutes.


Here is a picture of the original (my daily) air cylinder (on top) and the Trail Repair Cylinder I use (on the bottom.).





Notice the trail repair cylinder is physically smaller, and there is only one air hose fitting.


Armor

So far I have not had to do a trail repair but I would imagine it is only a matter of time.

My Ox Locker is in the rear of my Jeep and the Air Cylinder is fairly well protected. However a front Ox Locker with Air Cylinder is a different story. (Talk about leading with your chin!)

Here is a picture of John’s front Ox Locker converted to Air Operations along with the Armor he has installed.




The armor to protect the Front Ox Locker Air Cylinder is simply a modified U-channel , which bolts to a plate welded to the axle tube.

I have done a similar setup for a friend using muffler type clamp and base plate clamped around the axle tube and then bolting the modified U-channel to it.

As you can see protecting the air cylinder with some skid plate material isn’t all that difficult to do. The question becomes, it is needed.

In the front? Absolutely.

In the back? The jury is still out.

My rear Air Converted Ox Locker Air Cylinder has never been touched by a rock in the 18 plus months it has been installed. It will probably happen, and then I will do the 2-minute trail repair. (I’ll probably build some armor for it too at that time.) But until that happens. I’m a happy camper with the way I have it set up.

I hope this post has been helpful and informative to those who have x Lockers. If not today, perhaps in the future.

Have a nice night folks.

Frank