Lit. No. 40694, Rev. 04
30
May 1, 2021
MAINTENANCE
AIMING HEADLAMP BEAMS
Tighten headlamp fasteners to 45 ft-lb once correct
visual aim is achieved.
1. Place vehicle on a level surface 25 feet in front of
a matte-white screen, such as a garage door. The
screen should be perpendicular both to the ground
and to the vehicle centerline.
2. The vehicle should be equipped for normal
operation. The snowplow blade should be in place
and in raised position. Below are steps listed
by the Society of Automotive Engineers (SAE)
pertinent to headlamp aiming in speci
fi
cation
#SAE J599d.
3. Prepare vehicle for headlamp aim or inspection.
Before checking beam aim, the inspector will:
a. Remove ice or mud from under fenders.
b. Set tire in
fl
ation pressures to the values
speci
fi
ed on vehicle information label.
c. Check springs for sag or broken leaves.
d. See that there is no load in the vehicle other
than the driver and ballast as speci
fi
ed in the
Power Match selection system.
e. Check functioning of any automatic vehicle
leveling systems and speci
fi
c manufacturer's
instructions pertaining to vehicle preparation
for headlamp aiming.
f. Clean
lenses.
g. Check for bulb burnout and proper beam
switching.
h. Stabilize suspension by rocking vehicle
sideways.
4. Mark (or tape) the vertical centerline of the
snowplow headlamps and the vertical centerline
of the vehicle on the screen. Mark the horizontal
centerline of the snowplow headlamps on the
screen (distance from ground to snowplow
headlamp centers).
5. Align the top edge of the high-intensity zone of
the snowplow lower beam below the horizontal
centerline and the left edge of the high-intensity
zone on the vertical centerline for each snowplow
headlamp. (Refer to diagram below.)
Vertical Centerline Ahead of
DS Snowplow Headlamp
Align with Vehicle
Centerline.
Vertical Centerline Ahead of
PS Snowplow Headlamp
Screen Located 25 Feet
from Snowplow Headlamps
Horizontal Centerline
of Snowplow Headlamps
High-Intensity Zones of Snowplow Headlamps on Low Beam
