Air Lift LoadCONTROLLER/Dual 25852 User manual

MN-746 • (041202) • ECR 7259
For maximum effectiveness and safety,
pleasereadtheseinstructionscompletely
before proceeding with installation.
Failure to read these instructions can result in an
incorrect installation.
INSTALLATION GUIDE
Kits 25852
and 25856
Dual Gauge Analog
Compressor Systems
Kit #25852 with standard duty compressor
Kit #25856 with heavy duty compressor
LoadCONTROLLER / Dual ™

Introduction
The purpose of this publication is to assist with the installation of the Load Controller / Dual
onboard air management system.
Itisimportanttoreadandunderstandtheentireinstallationguidebeforebeginninginstallation
orperforming any maintenance,serviceorrepair. The informationhereincludes a hardware
list and step-by-step installation information.
Air Lift Company reserves the right to make changes and improvements to its products and
publications at any time. Contact Air Lift Company at [phone] or visiti us online at
www.airliftcompany.com for the latest version of this manual.
IMPORTANT SAFETY NOTICE
The installation of this kit does not alter the Gross Vehicle Weight Rating (GVWR) or payload
of the vehicle. Check your vehicle’s owner’s manual and do not exceed the maximum load
listed for your vehicle.
Gross Vehicle Weight Rating: The maximum allowable weight of the fully loaded vehicle
(including passengers and cargo). This number — along with other weight limits, as well
as tire, rim size and ination pressure data — is shown on the vehicle’s Safety Compliance
Certication Label.
Payload: Thecombined, maximum allowableweightof cargo andpassengersthatthe truck
is designed to carry. Payload is GVWR minus the Base Curb Weight.
NOTATION EXPLANATION
Hazard notations appear in various locations in this publication. Information which is
highlightedbyoneofthesenotationsmustbeobservedtohelpminimizeriskof personal injury
orpossible improper installationwhichmayrenderthe vehicle unsafe.Notesareusedto help
emphasize areas of procedural importance and provide helpful suggestions. The following
denitions explain the use of these notations as they appear throughout this guide.
INDICATES IMMEDIATE HAZARDS WHICH WILL RESULT IN SEVERE PERSONAL
INJURY OR DEATH.
INDICATES HAZARDS OR UNSAFE PRACTICES WHICH COULD RESULT IN SEVERE
PERSONAL INJURY OR DEATH.
INDICATES HAZARDS OR UNSAFE PRACTICES WHICH COULD RESULT IN DAMAGE
TO THE MACHINE OR MINOR PERSONAL INJURY.
Indicates a procedure, practice or hint which is important to highlight.
DANGER
NOTE
WARNING
CAUTION
Load Controller / Dual

Installation Diagram Adapter #1
Adapter #2
Adapter #3 *
Adapter
Fuse
* Uses 3/16 (smaller) Female Push On Connector
Check valves
Low pressure
sensors
Harness #1
Fuse box
Air springs
(previously installed)
Power wire
Power wire
Fuse adapter
In line
15 AMP fuse
Firewall
Grommet
(A1) Standard Duty Compressor
Ground
Relay
Ground
Analog Gauge
(A2) Heavy Duty Compressor
Ground
Check valves
Power wire
Filter
- OR -
g. 1
Load Controller / Dual

Item Part # Description ............................... Qty
A1 16060 Standard Duty Compressor ................1
A2 16092 Heavy Duty Compressor.....................1
B 25195 Analog Dual Gauge.............................1
C 26918 Harness, Dual Analog Gauge .............1
D 26042 Sensor, 5 PSI......................................2
E 20946 1/4” Air Line, “DOT”........................... 50’
F 25196 Gauge Mounting Kit ............................1
G 10463 Grommet.............................................1
H 24652 Spade Fuse, 15 Amp (ATC)................1
I 24539 Fuse Holder (ATC/ATO) .....................1
J 24752 Center Butt, 12-10 GA Shrink Tube....2
K 24524 3/16” Terminal, FSpd ..........................1
L 24595 FSpd Terminal, 12 GA ........................1
M 24543 Fuse, AGC Tap In ...............................1
N 24561 Mini Fuse Adapter...............................1
O 24542 ATC/ATO Fuse Tap In 1/4 ..................1
P 24594 1/4” Terminal, FSpd 16 GA.................4
Q 10466 8” Zip Tie.............................................5
R 21838 Tee Union 1/4” X 1/4” PTC .................2
S 17441 #8-18X1” Tek Screw ...........................2
T 26061A Y-Assembly.........................................1
U 21275 Tee, Hose & Check Valve...................2
Hardware List
Load Controller / Dual

Dual Analog Gauge Electrical Schematic
g. 2
Load Controller / Dual

Dual Analog Gauge Pneumatic Schematic
Colored tape can serve as an indicator for right and left springs when routing air lines.
NOTE
g. 3
Load Controller / Dual

Dual Analog Gauge Mounting Options
g. 4
Dual analog gauge mounting
hardware on bottom of gauge
g. 5
Dual analog gauge mounting
hardware on top of gauge
g. 6
Back of analog gauge
AirlinePower Wires
g. 7 Optional Dashboard Mounting
(Exploded View)
Load Controller / Dual

Installing the Load Controller / Dual System
RECOMMENDED COMPRESSOR LOCATIONS
Important
LOCATE COMPRESSOR IN DRY, PROTECTED AREA ON VEHICLE.
DIRECT SPLASH OR EXCESSIVE MOISTURE CAN DAMAGE
THE COMPRESSOR AND CAUSE SYSTEM FAILURE.
Disclaimer: If you choose to mount the compressor outside the vehicle please keep in
mind the compressor body must be shielded from direct splash and the intake should be
snorkeled inside the vehicle. If the compressor does not include a remote mount air lter or
if mounting the compressor outside the vehicle, make sure to orient the compressor intake
lter so that all moisture can easily drain.
Please also remember...
• To avoid high heat environments
• To avoid mounting the compressor under the hood.
• To check to be sure the compressor harness #2 will reach the compressor and connect
to harness #1.
• The compressor can be mounted in any position — vertical, upside down, sideways,
etc. (please refer to the instruction manual).
GETTING STARTED
If you are adding this control system to an Air Lift LoadLifter5000 application, then no
modications to the low pressure sensor are necessary. If you are adding this control system
to an Air Lift 1000 or RideControl application, and if your specic application requires a
minimum of 10 p.s.i., then it will be necessary to adjust the low pressure sensor to 10 p.s.i.
To increase the pressure in the low pressure sensor, remove the rubber plug with pliers
(g. 8). Using an allen wrench, turn the screw clockwise 4 1/4 turns (g. 9). Push the rubber
plug back into the top of the low pressure sensor. Proceed with the step by step installation
instructions.
g. 8
Remove
rubber cap
g. 9
Turn allen screw 4 ¼
turns clockwise
Load Controller / Dual

NOTE
CAUTION
STEP BY STEP INSTALLATION
We recommend that you install the air spring kit rst per the instructions provided with the
air spring kit.
1. Install the gauge pod (gs. 4, 5 & 6). Select a convenient mounting location that has a
sturdy rigid surface. The bottom edge of the dash on either side of the steering wheel is
agood location. Attachthegaugepod to theselectedlocationwith the blackself-tapping
screws.
Optional dash mounting bracket and hardware also included (g. 7).
2. Connect the harness to the gauge pod.
a. Connect the color coded wires to the gauge harness as shown in the attached
schematic (g. 2).
b. Connect the low pressure switch assemblies as shown in the attached schematic
(g. 2).
c. Do not connect the power wire at this time.
d. Thewiringharnessalsoconnectsthegaugepodtothelowpressuresensorassembly.
The low pressure sensor protects the air springs from failure resulting from low
pressure in the unloaded condition. This sensor is preset to maintain a MINIMUM
pressure of 5 psi in the air springs unless the setting was changed in the “Getting
Started” section. The sensor measures the pressure in each spring and turns on the
compressor if the pressure falls below the set psi.
e. Screw ground eyelet to rewall or other electrical ground in the cab.
The sensor should be located under the dash inside the vehicle and secured with the
provided tie straps.
3. Install the compressor unit.
a. Hold the compressor in the recommended location (g. 11 or 12).
b. For box frames: In some cases the frame section will not be wide enough to mount
the compressor legs at to the rail. Refer to gs. 11 and 12 in this situation.
DO NOT DRILL ANY HOLES INTO THE FRAME OR THE FLOOR BOARD BEFORE
CHECKING FOR HYDRAULIC LINES, GAS LINES, AND/OR ELECTRICAL WIRES
THAT MAY NEED TO BE MOVED ASIDE. ALSO, WHEN ATTACHING TO THE FLOOR
BOARD, IT IS IMPORTANT TO CHECK WHERE THE SCREWS PROTRUDE THROUGH
THE FLOOR BOARD. IT MAY BE NECESSARY TO TRIM OR COVER THE TOP OF THE
SCREWS INSIDE THE VEHICLE. A SEALER SHOULD BE USED AROUND THE SCREW
TO PREVENT THE ELEMENTS FROM ENTERING THE CAB AREA.
g. 10
Compressor side
Gauge side
Black (ground)
Gray
NOTE
Load Controller / Dual

STANDARDDUTYCOMPRESSORMOUNTING(FIG.1- A1, 11)
In some cases the mounting area does not provide enough room to use a drill to drive in
the screws. It may be necessary to use the mounting brackets as a template to drill 13/64”
holes through the frame rst and then use a 7/16” nut driver to install the self tapping screws.
HEAVY DUTY COMPRESSOR MOUNTING (FIG. 1 - A2, 12)
Using the compressor as a template, drill holes and mount the compressor using the black
mounting hardware that comes in the box containing the compressor.
Attach the compressor ground wire to one of the mounting screws (g. 1).
AIR LINE AND POWER WIRES ROUTING FOR
THE STANDARD DUTY COMPRESSOR:
1. Push the air line onto the barb tting on the compressor. Make sure the air line covers
all barbs. A small amount of water or lubricant and pushing with a slight circular motion
will ease installation (g. 13).
g. 13
Power (red) wires
Air line
Ground
Barbed tting/check valve
NOTE
g. 12
Frame
Floor plan
g. 11
Floor planFrame
L-bracket
Supplied self
tapping screw
¼” Bolt and nut will need to be
provided if the L-bracket is fabricated.
NOTE
NOTE
Load Controller / Dual

AIR LINE AND POWER WIRE ROUTING FOR
THE HEAVY DUTY COMPRESSOR:
1. Remove the nut from the leader hose and install over air line from check valve assembly.
2. Push the air line from the check valve assembly into the barbed tting on the compressor
leader hose.
3. Slide the nut over the tting and tighten securely (g. 14).
4. Route the harness to the compressor.
a. Use existing grommets in the oorboard or rewall to route the harness from the cab
to the frame mounted compressor.
b. In some cases, a hole may have to be drilled to allow access for the harness. Drill
a 1” diameter hole and install the provided grommet (g. 15). It will be necessary to
seal any grommets or holes that have been cut, drilled or removed so as not to allow
elements to enter the cab area of the vehicle.
c. When routing the wiring harness, it should not be routed so as to lay on, or near,
the exhaust pipe/mufer/catalytic convertor of the vehicle. Routing along the top of
a crossmember or over a heat shield is recommended.
5. The next connection is between each air spring and the air line “T” tting.
a. With the air springs deated, use a hose cutter to cut the air line already installed
between the air springs and the ination valves.
b. Install the provided “T” ttings (g. 1) by pushing the air line into each leg of the “T”
until you feel a denite “click”. Each line should go in 9/16”.
c. Connect a single length of air line to the open leg of the “T”. Connect as shown in
the pneumatic schematic.
d. Route the air line across the chassis from the far side over the exhaust system heat
shieldsand along theframeup to thecompressor.Avoid heat sources,sharpedges,
and tight bends.
g. 15
After the hole is drilled and before
you route the harness to through the
rewall, insert the grommet and “walk”
the material around the inside edge of
the drilled hole. You may have to trim
the grommet to get an exact t.
(The exible grommet is in the sealed
parts package.)
g. 14
(A2) Heavy Duty Compressor
Ground
Check valves
Power wire
Filter Leader Hose Compression Fitting
Load Controller / Dual

e. Route air lines into cab from “T” tting and attach to pressure switch assembly as
shown in the pneumatic schematic (gs. 3 and 10).
f. Route air lines from low pressure switch to gauge barb.
g. Press air line over gauge barb. Water or lube may assist in securing air lines over
the barb. A circular motion will assist in installation.
6. Connect the power wire to fused ignition.
a. Route it to the vehicle fuse box.
b. Determine which open terminal (accessory, etc.) works only when the key is in the
“on” or accessory position (or refer to the owners manual for an available accessory
fuse). The terminal should have an amperage rating higher than the 15 amp in-line
fuse.
c. Connection to the fuse terminal will depend on what type of fuse your vehicle uses.
If your vehicle uses the barrel type fuse, use adapter #1. If you have the standard
spade type fuses, use adapter #2. Many late model vehicles use a smaller spade
type fuse which requires adapter #3 (g. 16). If adapter #1 or #2 are used, it will be
necessary to cut off the ¼” female connector attached to the power wire and crimp
the smaller 3/16” female connector supplied with this kit.
Connect adapter to “HOT” side of the fuse. With the ignition on, the compressor will turn on
and ll the system to 10 p.s.i. before shutting off.
7. Press the off/on button to inate both air springs and use the small deate button to
adjust the pressure. Inate to 30 p.s.i. (20 p.s.i. for Air Lift 1000 kits). Check all ttings
and ination valve cores with a solution of 1/5 dish soap to 4/5 water in a spray bottle
for leaks.
IMPORTANT: If the compressor runs continually or often, then there is a leak. Disconnect
the compressor at the fuse box and test for leaks with a soapy water solution.
NEVER RUN THE COMPRESSOR LONGER THAN FOUR MINUTES CONTINUOUSLY.
ALLOW AT LEAST FIVE MINUTES FOR COOL DOWN BEFORE STARTING THE
COMPRESSOR AGAIN.
Adapter #1
Adapter #2
Adapter #3 *
Adapter
Fuse
* Uses 3/16 (smaller) Female Push On Connector
g. 16
NOTE
CAUTION
Load Controller / Dual

Frequently asked questions
Q. Will installing air springs increase the weight ratings of a vehicle?
No. Adding air springs will not change the weight ratings (GAWR, GCWR and/or GVWR)
of a vehicle. Exceeding the GVWR is dangerous and voids the Air Lift warranty.
Q. Is it necessary to keep air in the air springs at all time and how much pressure
will they need?
Theminimumairpressureshould be maintainedatalltimes. The minimumairpressure
keeps the air spring in shape, ensuring that it will move throughout its travel without
rubbing or wearing on itself.
Q. Is it necessary to add a compressor system to the air springs?
No.Airpressurecanbe adjusted with anytypeofcompressor as longasitcan produce
sufcient pressure to service the springs. Even a bicycle tire pump can be used, but
it’s a lot of work.
Q. How long should air springs last?
If the air springs are properly installed and maintained they can last indenitely.
Q. Will raising the vehicle on a hoist for service work damage the air springs?
No.Thevehiclecan beliftedon a hoistfor short-term servicework such astirerotation
oroilchanges. However, if thevehiclewillbeon the hoist foraprolongedperiodof time,
support the axle with jack stands in order to take the tension off of the air springs.
Tuning the air pressure
Pressure determination comes down to three things — level vehicle, ride comfort, and
stability.
1. Level vehicle
If the vehicle’s headlights are shining into the trees or the vehicle is leaning to one side,
then it is not level (g. 17). Raise the air pressure to correct either of these problems
and level the vehicle.
2. Ride comfort
If the vehicle has a rough and harsh ride it may be due to either too much pressure or
not enough (g. 18). Try different pressures to determine the best ride comfort.
3. Stability
Stability translates into safety and should be the priority,meaning the driver may need
to sacrice a perfectly level and comfortable ride. Stability issues include roll control,
bounce, dive during braking and sponginess (g. 19). Tuning out these problems
usually requires an increase in pressure.
Bad headlight aim
g. 17
Sway and body roll g. 19
Rough ride g. 18
Product Use Information
Load Controller / Dual

Guidelines for adding air:
1. Start with the vehicle level or slightly above.
2. When in doubt, always add air.
3. For motorhomes, start with 50-100 p.s.i. in the rear because it can be safely assumed
that it is heavily loaded.
4. If the front of the vehicle dives while braking, increase the pressure in the front air
bags, if equipped.
5. If it is ever suspected that the air bags have bottomed out, increase the pressure (g. 20).
6. Adjust the pressure up and down to nd the best ride.
7. If the vehicle rocks and rolls, adjust the air pressure to reduce movement.
8. It may be necessary to maintain different pressures on each side of the vehicle. Loads
such as water, fuel, and appliances will cause the vehicle to be heavier on one side
(g. 21). As much as a 50 p.s.i. difference is not uncommon.
g. 20
Bottoming out Unlevel Level g. 21
Load Controller / Dual
AIR LIFT SYSTEMS SUSPENSION SYSTEMS