Page 271 of 374

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
270 Vehicle Care
Headlamps and Front
Turn Signal
Replacing the Headlamps
When the bulb has blown out,
replace it with a bulb of the
specified wattage. Be careful not to
excessively tighten the mounting
screws when replacing the
headlamp bulbs.
Do not replace a bulb with other
than the specified wattage.
Proper aiming of the headlamps is
important to ensure sufficient
illumination of the highway without
blinding other motorists. When
replacing headlamp bulbs, have the
headlamp aim adjusted at your
dealer.
When replacing a bulb, make sure
the light switch is“OFF”.
See Bulb Replacement 0267.
1. Remove the front grille (3).
Remove the screw (4) from the
center of the grille. Push up on
the tabs of the five clips (1) on
the upper side of the grille and
pull the grille toward you to
remove it. Loosen the nuts (2)
for the turn signal light.2. Remove the turn signal lamp.Open the front door. Use a
phillips head screwdriver to
remove the two screws
between the door and the cab.
Page 272 of 374
Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 271
3. Tilt the turn signal lamp unitdown toward the front of the
vehicle and remove it.
4. Disconnect the connector (1)for the turn signal lamp from
the socket (2) and then remove
the lamp.
6. Disengage the rubber seals (2)
from the two projections (3) at
the bottom of the headlamp.
Remove the four bolts (1).
7. Disconnect the headlampconnector (5) and the parking
lamp socket (3). Remove the
headlamp assembly.
When removing the headlamp
connector, pull out the
connector while holding the
center portion of the rubber
boot. Otherwise, the headlamp
bulb will be broken.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 273
3. To install the lamps, performthe same sequence of
operations in reverse, taking
care to turn the connector
clockwise to lock it securely.
If the socket is not locked securely,
water could get inside the lamp and
lead to a breakdown.
Replacing a Front Turn
Signal Lamp
Do not replace a bulb with other
than the specified wattage. This will
cause abnormal flashing,
particularly for turn signal lamps.
When replacing a bulb, make sure
the light switch is OFF.
1. While referring to “Replacing
the Headlights”, tilt the turn
signal lamp assembly down
toward the front of the vehicle
and remove it.
2. Disconnect the connector for the turn signal light and then
remove the socket.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
274 Vehicle Care
3. Pull the bulb from the socketand replace it with a new one.
4. To install the lamps, perform the same sequence of
operations in reverse, taking
care to turn the connector
clockwise to lock it securely.
If the socket is not locked securely,
water could get inside the light and
lead to a breakdown.
Roofmarker Lamps
1. Loosen the screws (2) and remove the lens (1). 2. Remove the bulb (3) from the
socket (4) and replace it with a
new one.
3. To install the lights, follow the removal procedure in reverse.
If the screwing procedure is
inadequate, water may infiltrate into
the lamp unit.
Sidemarker Lamps
(Including Turn Signal
and Cornering Lamps)
Do not replace a bulb with other
than the specified wattage. This will
cause abnormal flashing,
particularly for turn signal lamps.
When replacing a bulb, make sure
the light switch is "OFF".
1. Open the front door, remove the rubber cap (1) in the lower
part of the door, and loosen
the nut (2).
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 275
2. Slide the cornering lamp (3)and the side turn signal lamp
forward relative to the vehicle.
Disconnect the clip (1) on the
lamp’s rear side from the door
panel (2) and pull out the lamp.
If you pull out the light rear
section by too much when
removing the clip on the rear
side, the clip on the lamp front
side may be damaged.
3. When the clip (1) has been
removed, pull the lamp out
while sliding it out toward the
rear of the vehicle. 4. Loosen the socket by turning it
counterclockwise.
5. Pull the bulb out from thesocket and replace it with a
new one.
6. To install the lights, perform the same sequence of operations
in reverse taking care of the
following points:
A. Turn the socket clockwiseto lock securely.
If the socket is not locked
securely, water could get
inside the light and lead to
a breakdown.
B. Insert the clip on the backof the rear part of the light
into the door panel.
C. Push the front part of the light into the door panel,
and insert the clip on the
back of the front part of the
light in the door panel.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
276 Vehicle Care
D. Open the front door, tightenthe nut from the inside of
the door, and install the
rubber cap.
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
1. Turn Signal Lamp
2. Taillamp/Stoplamp
3. Back-Up Lamp
4. Lens
1. Loosen the screws and remove the lens.
2. Loosen the bulb by turning it counterclockwise while
pressing on it.
3. To install the lights, follow the removal procedure in reverse.
License Plate Lamp
1. Bulb
2. Lens
3. Screw
4. Cover
1. Loosen the screws and removethe cover.
2. Remove the lens.
3. Loosen the bulb by turning it counterclockwise while
pressing on it.
4. To install the lights, follow the removal procedure in reverse.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Service and Maintenance 331
Recommended Daily
(Pre-operation) Inspections
These checks are in addition to, not
instead of, any legally required daily
inspections. See related topics
under "Maintenance Schedule",
especially if problems are found.
For safe and comfortable driving,
keep record of the distances driven
and the condition of the vehicle
during operation. Perform
inspections at appropriate intervals,
and perform maintenance in
accordance with the findings of the
inspections. If an inspection reveals
an abnormality or there was an
abnormality the previous time the
vehicle was driven, have the vehicle
repaired by the nearest dealer
before it is driven again.1. Components that showed abnormalities during the
previous operation
.Check components that
showed abnormalities
during the previous
operation 2. Checks performed at the
engine
.Fan belt looseness and
damage
. Engine oil level
. Engine coolant level
. Power steering fluid level
3. Checks performed from the driver's seat
.Brake fluid level
. Brake pedal free play
. Operation of meters,
gauges and warning/
indicator lights
. Engine startability,
abnormal noise and color of
exhaust gases
. Parking brake lever stroke
. Windshield washer fluid
spray condition and
windshield wiper
effectiveness
. Windshield washer fluid
level .
Steering wheel position and
free play
. Operation of horn and turn
signal lights
. Door lock operation
4. Checks performed during a walk around the vehicle
.Illumination, flashing,
contamination, damage and
obstruction of lights
. Contamination, damage ad
obstruction of windows,
mirrors and reflectors
. Leaf spring damage
. Oil, engine coolant, fuel,
brake fluid and power
steering fluid leaks
. Water separator
5. Checking wheels and tires .Air pressure
. Cracks and other damage
. Abnormal wear
. Tread depth
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
332 Service and Maintenance
.Mounting condition of all
wheel nuts
6. Checks performed after the engine startup
.Oil, engine coolant, fuel,
brake fluid and power
steering fluid leaks
. Inspect the exhaust system,
checking that the tailpipe is
clear
7. Checks performed while driving the vehicle
.Brake effectiveness
. Engine abnormal noises
Keep the Floor Around the Driver
Seat Clean and Tidy
{Warning
It is extremely dangerous to have
empty cans, empty bottles,
or other items rolling around on
the floor because they could get
trapped under the brake pedal
and prevent brake application. (Continued)
Warning (Continued)
For proper pedal operation, it is
also essential to lay floor mats
properly. Incorrectly installed floor
mats would hinder free movement
of the pedals.
Do not use the dashboard pocket
or the top of the dashboard as a
place to put items that could roll,
which could interfere with your
driving. You and others could be
seriously injured.
Choose Your Footwear Suitable
for Driving
{Warning
Choose footwear that ensures
proper operation of pedals when
driving the vehicle. Use of
footwear unsuitable for driving
may cause an accident. The
driver could be seriously injured
when not wearing the proper
footwear.
Electrical System
Following the after-delivery service,
it is the owner's responsibility to
check all wiring periodically for
cracked, chafed or oil-soaked
insulation and maintain it in a clean
and tight condition to ensure
satisfactory operation of the
electrical system.
Headlights and Turn Signal
Lights
Turn the engine control switch to the
"ON" position, and then check the
way in which the headlights, turn
signal lights, and other exterior
lights come on and flash. In
addition, press the brake pedal to
confirm whether the stop lights
come on, and shift the transmission
to "R" position to confirm whether
the back up lights come on. Also
examine the lights for discoloration,
damage, and looseness.