Volvo VHD - Manual (Page 266)

260 Axles and Wheels
Auxiliary Lift Axle
Before raising or lowering any of the
auxiliary axles, be certain no one can be
trapped by the axle movement. Failure
to do so can result in a person being
trapped between the wheel and the body,
or between the wheel and the ground,
resulting in serious personal injury or
death.
Vehicles may be equipped with auxiliary
lift axles. The lift mechanism operates with
air pressure. To lower or raise the axle(s),
press the top part of the switch in to raise
the axle and press the lower part of the
switch in to lower the axle.
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Regulators for adjusting the air spring pres-
sure are located on the outside of the cab,
below the rear corner of the driver side
door. Regulators are operated by turning the
knob counter clockwise for lowering pres-
sure, and clockwise for increasing pressure.
CAUTION
Do not rely on gauges to determine
axle pressure. Weight must be verified
on scales, and pressure in the air springs
should then be adjusted accordingly.
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