Lit. No. 68251, Rev. 09
33
May 1, 2021
HEADLAMP AIMING
Fully tighten the headlamp fasteners once correct
visual aim is achieved.
1. Park the vehicle on a level surface 25 feet in front
of a matte-white screen, such as a garage door.
The screen should be perpendicular to both the
ground and 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 the vehicle for headlamp aim or inspection.
Before checking headlamp 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 the 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 the functioning of any automatic vehicle
leveling systems and speci
fi
c manufacturer's
instructions pertaining to vehicle preparation
for headlamp aiming.
f. Clean the lenses.
g. Check for bulb burnout and proper beam
switching.
h. Stabilize the suspension by rocking the
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
