SECTION 11: REAR AXLES
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version – Rev.2 April 2016)
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extended period. Raising tag axle increases
load on the drive axle, suspension and tires.
Do not drive vehicle with tag axle raised when
speed is exceeding 12mph (20 km/h).
In order to prevent damage to the suspension,
always raise the tag axle before lifting the
coach.
2.3
RETRACTING TAG AXLE FOR REPAIR
PURPOSES
Connect an external air pressure line to the
emergency fill valve in the engine
compartment.
Lift the axle by pushing the lever forward.
WARNING
Install a protective cover to prevent unfortunate
lever operation while work is being carried out
under the vehicle.
Raise the vehicle using the lifts.
WARNING
Lift manufacturers recommend lowering the
vehicle to the ground or installing some safety
stands before activating the suspension to
prevent the lifts from becoming unstable.
For added safety, install nylon slings over
tag axle shock absorbers.
2.4 GREASE
LUBRICATED
WHEEL
BEARINGS
The unitized hub bearings used on the NDS
range of axles, are non-serviceable items.
Bearings are pre-adjusted, lubricated and have
seals fitted as part of the manufacturing process.
The bearings are greased for life and there is no
need or facility for re-lubrication.
MAINTENANCE
Front and tag axle hub bearings need to be
checked at intervals of 30,000 miles (48 000
km) or twice a year whichever comes first.
NOTE
For more information on front and tag axle
wheel hub, refer to “DANA SPICER Service
Manual NDS Axle Range” found in the OEM
manuals folder.
2.5
REMOVAL AND INSTALLATION
2.5.1
Removing Tag Axle Only
The following procedure deals with the removal
of the tag axle while keeping the air springs
installed. The method used to support the axle
and suspension components during removal and
disassembly depends upon local conditions and
available equipment.
Connect an external air pressure line to the
emergency fill valve in the engine
compartment.
Lift the axle by pushing the lever forward.
WARNING
Install a protective cover to prevent unfortunate
lever operation while work is being carried out
under the vehicle.
Disconnect tag axle air springs pneumatic
hoses and install valves or plugs.
Raise the vehicle using the lifts.
Dismount tag axle components.
Before reinstalling air spring hoses, make
sure there is no pressure left inside by
opening the valves or unloading tag axle.
2.5.2
Removing Tag Axle Along With
Suspension Components
The following procedure deals with the removal
of the tag axle assembly along with the
suspension components. The method used to
support the axle and suspension components
during removal and disassembly depends upon
local conditions and available equipment.
1. Raise vehicle by its jacking points on the
body
.
Place jack under frame. Remove drive
axle wheels (if required, refer to Section 13,
"Wheels, Hubs and Tires"
).
2. Exhaust compressed air from the air supply
system by opening the drain cock on each air
reservoir and deplete air bags by moving
leveling valve arm down.
3. Install jacks under tag axle jacking points to
support the axle weight (refer to figure 8).
