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RD109 DANA 44, 35 SPLINE, 3.92 & UP AIR OPERATED LOCKING DIFFERENTIAL INSTALLATION GUIDE...
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No liability is assumed for damages resulting in the use of the information contained herein. ARB Air Locker Air Operated Locking Differentials and Air Locker are trademarks of ARB Corporation Limited. Other product names used herein are for identification purposes only and may be trademarks of their respective owners.
Table of Contents: 1 Introduction 1.1 Pre-Installation Preparation 1.2 Tool-Kit Recommendations 2 Removing the Existing Differential 2.1 Vehicle Support 2.2 Differential Fluid Drain 2.3 Disconnecting the Axles 2.4 Marking the Bearing Caps 2.5 Checking the Current Backlash Amount 2.6 Removing the Differential Center 3 Installing the Air Locker 3.1 Insuring Adequate Oil Drainage 3.2 Installing the Carrier Bearings...
Although your ARB Air Locker comes complete with all the step by step instructions you will need to supplement your vehicle manufacturer’s service manual and install your new differential, ARB recommends that you have your Air Locker installed by a trained professional.
Either a replacement gasket, or gasket sealant, for your differential cover. A sufficient volume of differential oil to completely refill your housing. (see the ARB Air Locker Operating and Service Manual for recommended lubricants) A soap and water mixture to test for air leaks.
2 Removing the Existing Differential Vehicle Support Safely secure the vehicle on a hoist. We recommend supporting the vehicle on a chassis hoist to keep the differential area at a convenient working height and to leave the wheels and axles free to be rotated and removed.
Any misalignment of the axle tubes may result in excessive wear and/or failure of your differential and axle shafts. ARB strongly recommends that you have your axle assembly inspected for concentricity and straightness before installing your Air Locker.
2 Removing the Existing Differential Checking the Current Backlash Amount IMPORTANT: This step is a precautionary measure recommended by ARB due to the fact that some after market ring and pinion sets have been manufactured to run with different backlash settings than those specified by your vehicle manufacturer.
2 Removing the Existing Differential Removing the Differential Center IMPORTANT: YOU MUST SPREAD THE HOUSING ON CAST IRON MODELS Spreading the differential housing with a differential case spreader is a step which is critical to set up bearing pre-load on cast iron differential housings (See Figure 3.). Improper pre-load will result in undue bearing wear, increased stresses in the differential center, increased running noise, and ultimately, ring and pinion gear damage.
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2 Removing the Existing Differential NOTE : The differential center is heavy and quite difficult to handle when covered in oil. Take care not to drop it. Relieve any tension on the spreader immediately after the differential has been removed. NOTE : Some Dana 44 type differentials now come from the factory equipped with an OE master shim on the...
3 Installing the Air Locker Insuring Adequate Oil Drainage IMPORTANT: Some Salisbury axles were manufactured with poor oil drainage between the axle tubes and the differential housing. This can often result in one of the axle tubes filling up with differential oil while running.
3 Installing the Air Locker NOTE : Make sure any grinding dust, filings or drill chips left behind by cutting the drainage slots is completely cleaned out of the housing. Check that the axle air vents are clear and working correctly. Installing the Carrier Bearings ...
3 Installing the Air Locker Approximate Backlash Shimming In order to reproduce a similar pre-load and ring and pinion backlash in your Air Locker to that of your original differential, measurements need to be taken so that a shim thickness can be calculated. ...
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Be sure to measure using the bearing cup that originally came off of the right-hand side. Assemble the new bearing cup and ARB master shim (supplied with your Air Locker kit) onto the right-hand side of the Air Locker (as shown in Fig.
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Select shims from the shim kit supplied with your Air Locker to make the thickness ‘B’ as determined above. Place this shim pack between the ARB master shim and the bearing cup. Re-measure the new distance ‘C’ from the Air Locker (now including the shim pack ‘B’) to make sure that it matches ‘A’...
3 Installing the Air Locker Mounting the Ring Gear IMPORTANT: Dana 44 ring gears may use either 3/8”, 7/16”, or 1/2” bolts. For 7/16” bolts re-drill Air Locker flange to 11.5mm [29/64”]. For 1/2” bolts re-drill Air Locker flange to 13.0mm [33/64”]. ...
3 Installing the Air Locker Drilling and Tapping the Bulkhead Port An airline port must be drilled and tapped through the differential housing to mount the bulkhead fitting into. NOTE : Higher ratio gearing uses deeper (thicker) ring gears with teeth that extend much further. Make sure the intended hole location is far enough away from the ring gear teeth that the air line will not be at risk of contact with the current or future ring gears.
Assemble a bearing cup onto the left-hand side of the Air Locker. Assemble one of the two ARB master shims (included with the Air Locker shim kit) onto the stepped face of the seal housing with the rounded edge of the shim facing out.
Figure 10. Insert and hold the Air Locker into the differential housing. Insert the remaining ARB master shim from the Air Locker shim kit between the right-hand bearing cup and the bearing seat of the axle housing with the rounded edge of the ARB master shim facing away from the center.
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NEVER machine the Air Locker. Remove the Air Locker from the axle housing. Install the shim pack ‘D’ between the ARB master shim and the seal housing as shown in Figure 9. Spread the differential housing again (Refer to Section 2.6).
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3 Installing the Air Locker Figure 12. Release all spreader tension. Check that some backlash can be felt between the ring and pinion gears. No backlash would be an early indication of incorrect shim thickness.
3 Installing the Air Locker Reinstalling the Bearing Caps IMPORTANT: The ARB master shim must be assembled between the stepped side of the seal housing and the bearing cup. NOT HAVING THE ARB MASTER SHIM IN PLACE HERE WILL CAUSE BEARING FAILURE.
3 Installing the Air Locker Checking the Backlash Set a depth indicator on one of the ring gear teeth as in Figure 14. While supporting the pinion gear by holding the drive shaft, rotate the differential in both directions while observing the maximum variation in depth from the indicator (i.e., the highest value minus the lowest value).
3 Installing the Air Locker Re-Shimming the Backlash 3.9.1 NOTE : This step is only necessary when adjusting for incorrect backlash. Remove the bearing caps. Remove the differential as before. NOTE : Never spread the housing on the aluminum models. ...
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3 Installing the Air Locker Figure 15. NOTE : Excessive tightening of the center compression nut is not necessary to form a good seal around the tube and may damage the O-ring, the seal housing tube, or the threads of the compression nut. NOTE : Make sure the seal housing tube is all of the way into the center compression nut while you are tightening...
3 Installing the Air Locker Profiling the Seal Housing Tube 3.11 Completely remove the differential spreader. Without using sharp, jagged tools such as pliers (usually your hands are the best tool for this job), gently bend the seal housing tube so that it runs along the inside of the differential housing as shown in Figure 16.
Installing the Air System Mounting the Solenoid Connection to an ARB Air Compressor 4.1.1 (Fig.17.) Remove one of the 1/8” BSP plugs from its port in the compressor tank. Apply Teflon paste to the nipple (1/8” X 1/8” BSP) and insert it into the port and tighten.
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For ease of installation, quality of air supply, and a high level of dependability from your Air Locker(s) , ARB strongly recommends use of a genuine ARB Air Compressor, however, the Air Locker air system can be operated on any alternate air source that meets each of the following guidelines: ...
Installing the Air System Running and Securing the Air Line The path taken by the air line from your air source (i.e., compressor) to your Air Locker is unique to your vehicle and the position of your air source. Plan ahead carefully when running the air line and always follow these guidelines: ...
Installing the Air System To attach the air line to the push-in fitting of the solenoid; insert the line firmly into the fitting, pull outward on the flange of the fitting while holding the line as far into the fitting as possible, and then gently pull outward on the air line to clamp the line in place.
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Installing the Air System Screw on the outer compression nut and tighten, while supporting the center compression nut with a 3/8” spanner. The airline is now attached to the center compression nut. NOTE : The outer compression nut will tighten against a stop. Over tightening will not create a better seal.
Switch(es) should not be mounted where they will be exposed to water (e.g., in the lower section of an inner door panel). ARB recommends that you apply the Air Locker Warning Sticker (ARB part # 210101) within close visual proximity of the switch location.
Connection to an ARB Air Compressor 5.2.1 When wiring the Air Locker actuator switch(es) and solenoid(s) to an ARB Air Compressor, all connections can easily be set up directly from the supplied wiring loom. (Fig. 20.) NOTE : Refer to your ARB Air Compressor Installation Guide...
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5 Mounting & Connecting the Electrical System ARB AIR COMPRESSOR WIRING LOOM Figure 20. SWITCH TERMINAL IDENTIFICATION Figure 21.
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5 Mounting & Connecting the Electrical System Connection to an Alternate Air Source 5.2.2 When connecting the actuation switch to an alternate air source, the switch(es) should be wired according to figures 22. and 23., depending on whether one or two Air Lockers will be installed in the vehicle. Single Air Locker System 5.2.2.1 ...
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5 Mounting & Connecting the Electrical System Dual Air Locker System 5.2.2.2 If two Air Lockers are to be installed in the system, ARB recommends that the switches and solenoids be wired according to figure 23. For safety reasons, this configuration allows SOLENOID 2 to be actuated only if SOLENOID 1 is already on.
Testing & Final Assembly Leak Testing With the vehicle parked and the engine off, turn the compressor on and wait until the air system is fully charged. NOTE : With the Air Locker(s) disengaged, the air source (i.e., compressor) should not have to recharge over time. Intermittent recharging without Air Locker use usually indicates a leak at the solenoid fittings or at the compressor tank O-ring seal.
The wheels should again rotate in opposite directions. Re-Sealing & Filling the Differential NOTE : Consult the ARB Air Locker Operating & Service Manual for recommendations on differential lubricant specifications. Replace the differential cover using gasket sealant or a new standard differential cover gasket for your make of vehicle.
Testing & Final Assembly Post-Installation Check List Now that the Air Locker installation has been completed, ARB recommends that you take the time to complete the following check list just to insure that you haven’t missed any of the vital steps.
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