ARB RD151 User manual

`
RD151
TOYOTA 8” IFS, 34 SPLINE,
58MM CARRIER BEARING
AIR OPERATED
LOCKING DIFFERENTIAL
INSTALLATION GUIDE

No liability is assumed for damages resulting in the use of the information contained herein.
ARB AIR LOCKER 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.
ARB 4x4 ACCESSORIES
Corporate Head Office
42-44 Garden St Tel: [phone]
Kilsyth, Victoria Fax: [phone]
AUSTRALIA
3137
Australian enquiries [email protected]
North & South American enquiries [email protected]
Other international enquiries [email protected]
www.arb.com.au

Table of Contents:
1
1 Introduction
3
1.1
Pre-Installation Preparation
3
1.2
Tool-Kit Recommendations
4
2 Removing the Existing Differential
5
2.1
Vehicle Support
5
2.2
Differential Fluid Drain
5
2.3
Removing the Differential Assembly
5
2.4
Checking the Current Backlash Amount
6
2.5
Removing the Differential Center
7
3 Installing the Air Locker
8
3.1
Installing the Carrier Bearings
8
3.2
Approximate Backlash Shimming
9
3.3
Mounting the Ring Gear
12
3.4
Installing the Bearing Sleeves
13
3.5
Preload Shim Measurement
15
3.6
Calculation & Selection of Preload Shims
17
3.7
Drilling & Tapping the Bulkhead Port
17
3.8
Installing the Seal Housing
19
3.9
Setting Up the Bulkhead Fitting
22
3.10
Final Assembly
23
3.11
Checking the Backlash
24
3.12
Bench Testing the Air Locker
26
3.13
Reinstalling the Differential Assembly
27
4 Installing the Air System
28
4.1
Mounting the Solenoid
28
4.2
Running & Securing the Air Line
30
4.3
Connection to the Bulkhead Fitting
31
5 Mounting & Connecting the Electrical System
32
5.1
Mounting the Actuator Switch(es)
32
5.2
Wiring the Actuator System
33
6 Testing & Final Assembly
36
6.1
Leak Testing
36
6.2
Testing the Air Locker Actuation
36
6.3
Re-Sealing & Filling the Differential
37
6.4
Post-Installation Check List
38
7 Parts List
39
7.1
Exploded Assembly Diagram
39
7.2
Specifications
39
7.3
Itemized Parts List
40

2

1 Introduction
3
IMPORTANT :
BEFORE ATTEMPTING TO DISMANTLE YOUR VEHICLE FOR THIS
INSTALLATION, PLEASE READ THIS INSTALLATION GUIDE IN ITS
ENTIRETY, AS WELL AS ALL APPLICABLE SECTIONS OF YOUR
VEHICLE MANUFACTURER’S SERVICE MANUAL.
1.1 Pre-Installation Preparation
This booklet is to be used in conjunction with your vehicle
manufacturer’s service manual. ARB endeavors to account for every
possible variation in vehicle model when publishing its installation
guides, and guides are updated regularly as new model information
becomes available, however, the rapid and globally varied release of
some vehicles makes it difficult to insure that your vehicle model has
been accurately accounted for. In the case of any technical
discrepancies between this guide and your service manual, we
strongly advise that you adhere to the specifications and techniques
as documented in your service manual.
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. Many ARB distributors around the world have been fully
instructed in Air Locker installations by ARB, and have gained a wealth
of experience and skill from years of performing similar installations.
Once you begin this installation your vehicle will be immobile until all
steps of the installation are complete. Make sure your Air Locker kit is
the correct model for your vehicle and that it contains all of the parts
listed on back cover of this booklet. Also be sure you have
appropriately equipped yourself with all the necessary tools, parts, and
materials to complete this installation (see Section 1.2 Tool-Kit
Recommendations), and that you have allowed for an appropriate
amount of vehicle down time.
HINT : Place a mark inside each of the symbols as
you complete each step. It is very important NOT to
miss any of the steps!

1 Introduction
4
1.2 Tool-Kit Recommendations
Below is a list of tools and supplies you may need to complete this
installation. Requirements for your vehicle may vary. Please consult
your vehicle service manual for additional recommendations.
1.2.1 Tools
Standard automotive sizes (metric and/or imperial) of sockets,
wrenches, allen keys, and drills.
A dial indicator or other suitable measuring tool for checking ring &
pinion backlash.
NOTE : Split ‘clamshell’ type Toyota differential housings
require a long series dial indicator to check backlash.
A razor knife for nylon tubing.
A torque wrench (See vehicle service manual for required torque
range)
A lubricant drain reservoir.
A slide hammer for removing CV axles.
Suitable measuring tools to measure a differential for preload
shimming. (e.g., an automotive feeler gauge)
An 11.2mm [7/16”] drill and ¼”NPT tap for bulkhead fitting
installation.
An automotive bearing puller (e.g., ARB Bearing Puller #0770001).
A bearing press or arbor press.
1.2.2 Supplies
Thread lubricant/sealant compound (e.g., LOCTITE #567)
Thread locking compound (e.g., LOCTITE #272)
High strength retaining compound (e.g., LOCTITE #620)
A gasket sealant or replacement gasket for your differential.
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.
A selection of differential bearing shims to set-up preload and
backlash.

2 Removing the Existing Differential
5
2.1 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.
Once supported in the air, chock the wheels (if necessary) and
leave the vehicle in neutral.
2.2 Differential Fluid Drain
Position a fluid drain reservoir under the differential.
Remove the drain plug and drain all of the oil from the housing.
HINT : This is a good time to check for metal particles in
your oil and on the end of the magnetic drain plug which
may indicate a worn bearing or differential component.
Once drained, reinstall the drain plug.
2.3 Removing the Differential Assembly
Remove the stub axles from the differential housing according to
your vehicle manufacturer’s service manual.
NOTE : Rubber oil seals can be easily damaged. Support the
weight of the axle when extracting it across the edges
of the seals.
NOTE : Some Toyota IFS axles can be removed easier by
disconnecting the lower ball joint bracket.
HINT : Toyota IFS axle stubs are retained with a snap ring
which is considered to be a one-use part. Keep two of
these clips on-hand in case the clip(s) are damaged or
sheared off while removing the stub axle. Make sure all
of the remains of the clips are accounted for so that
they cannot damage differential components and seals.
Disconnect the drive shaft from the drive pinion flange.
Completely remove the entire differential assembly.

2 Removing the Existing Differential
6
2.4 Checking the Current Backlash Amount
IMPORTANT:
This step is a precautionary measure recommended by ARB due
to the fact that some aftermarket ring and pinion sets have been
manufactured to run with different backlash settings than those
specified by your vehicle manufacturer. Although ARB must
recommend you set backlash according to your service manual
guidelines, we also advise that you compare the backlash
measurements taken here to the recommended backlash settings
in your vehicle service manual. Measurements found to be
outside of your service manual recommendations may indicate
the need to deviate from those settings in order to achieve quiet
running with a good contact mark.
Refer to your vehicle service manual or your local authorized
ARB installer for more information.
Set a long series lever type dial indicator on one of the ring gear
teeth. Access to the ring gear teeth is gained through the oil drain
hole. (Refer to Figure 1.)
Figure
1.
Insert a large flat screwdriver or pry-bar through one of the axle
stub holes so that it wedges between the cross shaft and the carrier
body so that the differential center can be rotated by the cross
shaft, and not by the spline of one of the differential gears.
While supporting the pinion gear by holding the drive shaft flange,
rotate the differential in both directions (with the screwdriver or pry-
bar) while observing the maximum variation in depth from the
indicator (i.e., the highest value minus the lowest value). This value
is referred to as the ring and pinion backlash.
Rotate the differential center 90and measure again for accuracy.
Record the average of all measurements.

2 Removing the Existing Differential
7
2.5 Removing the Differential Center
Remove the floating shaft (or ADD unit if present) from the side of
the differential housing.
NOTE : The floating shaft or stub axle is retained by the same
type of clip that was used to retain the outer stub axle.
A slide hammer may be required for safe removal.
Refer to your vehicle manufacturer’s service manual.
Remove all bolts from around the outside of the clamshell.
Gently pry the clamshell apart and remove the differential center.
ARB recommends removing the oil seal from the deep clamshell half
at this stage. A replacement seal will be required (Toyota Australia
part #9031147012).
Using an arbor press, remove both bearing cups and preload shims
by pressing on the face of the shims through the housing from the
outside.
HINT : Heating each half of the clamshell (in an oven or with
a heat gun) to approx 130°C will allow the bearing
cups to fall straight out.
NOTE : Be sure not to mix up the left and right hand preload
shims. Later it will be necessary to know which shim
came from which side to assist in setting preload and
backlash.

3 Installing the Air Locker
8
3.1Installing the Carrier Bearings
Apply a thin film of high pressure grease to both bearing journals of
the Air Locker.
Using a bearing press or arbor press, press one of the supplied
tapered roller bearing cones onto the bearing journal opposite to
the ring gear flange of the differential carrier (As shown in Figure 2.)
until the bearing seats firmly against the bearing journal shoulder.
Figure
2.
Invert the Air Locker and press the second supplied bearing cone
onto the bearing journal on the ring gear flange side of the
differential (the seal housing side) until the bearing seats firmly
against the bearing journal shoulder.

3 Installing the Air Locker
9
3.2Approximate 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.
Secure the original differential to a work bench.
Remove the bolts that hold the ring gear in place.
Using a plastic or copper hammer, tap in a circle around the ring
gear to separate it from the differential carrier.
Figure
3.
Assemble the original bearing cup and OE Master Shim onto the
cone of the right-hand side of the original differential carrier.

3 Installing the Air Locker
10
Using a caliper or similarly accurate measurement method
(i.e., able to take accurate measurements within 0.04mm [0.0015”]),
measure the distance from the shoulder of the outer face of the OE
master shim to the ring gear mounting face (shown as ‘A’ in Figure
3.) and record this measurement as ‘A’.
NOTE : Be sure to measure using the bearing cup that
originally came off of the right-hand side.
Assemble the new bearing cup and 3mm thick ARB master shim
(supplied with your Air Locker kit) onto the right-hand side of the Air
Locker (as shown in Fig. 4.) and measure the total distance ‘C’.
NOTE : The shim pack ‘B’ should not be installed at this time.
Figure
4.
Record this measurement as ‘C’.

3 Installing the Air Locker
11
The thickness of the shim pack ‘B’ should make the distance ‘C’ on the
Air Locker closely match the distance ‘A’ on the existing differential
(within 0.1mm [0.004”] ).
Use the following calculation to find the desired thickness of ‘B’:
A –C = B (Replacement Shim Pack)
HINT : If your calculations are correct then the following
equation will also be true:
A –B –C = ZERO
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’ on the
original differential.
NOTE : NEVER machine the Air Locker.

3 Installing the Air Locker
12
3.3 Mounting the Ring Gear
Apply a thin film of high pressure grease to the ring gear shoulder
of the Air Locker to prevent seizing.
Thoroughly clean any thread locking compound or other foreign
matter from the holes of the ring gear, the threads of the ring gear
bolts, and the mating surfaces between the ring gear and the Air
Locker flange.
HINT : Stoning the ring gear mounting face before installation
will remove any high spots around the threads.
Heat the ring gear to between 80 and 100C [175 - 212F] in hot
water or in an oven to slightly expand the gear and facilitate
assembly.
NOTE : NEVER HEAT GEARS WITH A FLAME! This could
damage the hardened surface of the gear and result in
premature wear or failure.
Dry the gear and bolt holes with compressed air (if wet).
Install the ring gear onto the Air Locker by aligning the bolt holes
and then gently tapping it around in a circle with a soft mallet.
Avoid using the bolts to pull down the ring gear as this puts excess
strain on the bolts and the differential flange.
Apply a thread locking compound to the thread of each ring gear
bolt before inserting it. Do not apply threading compound directly
into the threaded hole as this could prevent the bolt from reaching
its full depth.
Tighten the ring gear bolts in a star pattern with a torque wrench
according to your vehicle manufacturer’s specified torque.

3 Installing the Air Locker
13
3.4Installing Bearing Sleeves
Using an oven or heat gun, heat both of the clamshell halves to
between 130° and 150°C to expand the housings.
Make sure that the bearing sleeves (Fig. 6.) and clamshell halves
are clean and free from any contaminants (e.g., water, dirt, metal
filings, etc.).
Apply Loctite 620 retaining compound (Fig. 5.) to the outside of
each bearing sleeve, just below the knurl.
Using a bearing press or arbor press, install the bearing sleeves.
Press them down until they have completely seated at the bottom
of the bearing bore (Fig. 7. & 8.).
HINT : If the clamshell halves are hot enough, the sleeves
should install with minimal press fit.
NOTE : Use a feeler gauge to ensure that the bearing sleeve
has been completely seated.
Figure
5.
Figure
6.

3 Installing the Air Locker
14
Figure
7.
Figure
8.

3 Installing the Air Locker
15
3.5 Preload Shim Measurement
In order to preload the tapered roller bearings in your Air Locker,
measurements need to be taken so that a value can be calculated for
the total shim thickness ‘D’in Figure 9.
Figure
9.
Assemble the 3mm ARB master shim and the shim pack
determined earlier as ‘B’(Fig.4.) into the bearing bore of the deep
half of the clamshell.
Using a bearing press or arbor press, press the appropriate bearing
cup into the bottom of the same bearing bore (i.e., until it stops
against the shim pack).
HINT : You should not be able to rotate the shim pack
underneath the bearing cup if it has been pressed in
far enough.
With the deep half of the clamshell sitting firmly on a horizontal
surface, set the Air Locker into the bearing cup inside the clamshell.
Bend the seal housing tube so that it points straight away from the
seal housing flange.

3 Installing the Air Locker
16
Assemble any remaining shims from the Air Locker shim kit
(supplied) together into one shim pack and measure the total
thickness. Include the remaining ARB Master Shim in this
measurement.
Assemble the shim pack onto the seal housing flange on the same
side as the seal housing tube’s solder joint.
Assemble the seal housing into the bearing bore in the shallow half
of the clamshell (shims against the clamshell).
Using a bearing press or arbor press, press the remaining bearing
cup into the bottom of the same bearing bore (until it stops against
the seal housing).
Carefully assemble the shallow half of the clamshell over the top of
the Air Locker.
Measure the preload gap that exists between the two halves of the
clamshell housing with a feeler gauge. (Refer to Fig.10.)
Figure
10.
NOTE : The preload gap should be the same when measured
all the way around the housing. If this is not true, then
reposition the shallow clamshell half and re-measure.
Subtract the amount measured at the preload gap from the
thickness of the shim pack placed onto the seal housing flange.
Record the result as this is your true ‘end float’ amount.

3 Installing the Air Locker
17
3.6 Calculation & Selection of Preload Shims
Consult your vehicle manufacturer’s service manual to determine
the carrier bearing preload amount specified for your vehicle.
NOTE : If your service manual specifies preload in terms of a
torque value measured off the drive pinion flange,
then assume a preload amount of 0.6mm [0.024”] for
the following calculations. Once you have assembled
the housing to check the final backlash (Refer to
Section 3.12 Checking the Backlash) you should verify
that your preload is correct using a torque wrench and
your service manual’s table of values.
Add the specified preload amount to the end float measurement
determined with the feeler gauge to determine a shim amount for
‘D’(Refer to Figure 9.).
PRELOAD + END FLOAT = SHIM PACK
Create a shim pack ‘D’ to closely match the measured amount.
NOTE : Do not add shims between the bearing cone and the
bearing seat and NEVER machine the Air Locker.
3.7 Drilling & Tapping the Bulkhead Port
A port must be drilled and tapped through the shallow half of the
clamshell to allow the seal housing tube through the housing to
connect with the air line from the air compressor.
Remove the Air Locker from the housing.
Press the shims, seal housing and bearing cup out of the bearing
bore of the shallow half of the clamshell.
Mark a spot on the shallow half of the clamshell in the same
position shown in the photographs in Figure 11. and Figure 12.

3 Installing the Air Locker
18
Figure
11.
Figure
12.
NOTE : To best determine the correct vertical position of the
drilled hole, measure down from the machined face
(shown at the top of the picture in Figure 12.) a
distance of 15mm [19/32”] and mark the horizontal line
which the hole is centered on.