Page 161 of 382
Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
160 Driving and Operating
SymptomCauseCorrective Action Reference
Not enough engine power Parking brake not fully
released
Make sure it is fully
released
-
Brake dragging
4-
Air cleaner clogged
4-
Fuel filter clogged
4-
Engine control system
faulty
4-
Common rail system
faulty
4-
Engine faulty
4-
DPF clogged
4-
Brakes not effective Drum-to-lining gap too
large
4-
Air in brake fluid
4-
Brake system failure
4-
Page 162 of 382
Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 161
SymptomCauseCorrective Action Reference
Uneven braking Unbalanced air pressure
in tires
Adjust to proper air
pressureSee
Wheels and
Tires 0295
Tire unevenly worn Replace tire See
Wheels and
Tires 0295
Drum brake out of
adjustment
4-
Poor wheel alignment
4-
Exhaust brake not working The electrical system is
faulty
4-
Steering wheel hard to turn Loaded too far forward Load properly -
Power steering fluid level
too low
Add fluidSee
Power
Steering Fluid
0 262
Insufficient air in front
tires Adjust to proper inflation
pressureSee
Wheels and
Tires 0295
Page 163 of 382
Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
162 Driving and Operating
SymptomCauseCorrective Action Reference
Excessive play in the steering wheel Wheel studs and nuts
loose
Tighten to the specified
torqueSee
Wheels and
Tires 0295
Unbalanced inflation
pressure in the tires Adjust to proper inflation
pressureSee
Wheels and
Tires 0295
Unbalanced tires
4-
Excessive steering
wheel free play
4-
Poor steering wheel return Poor lubrication in the
steering mechanisms
Lubricate the
mechanism
-
Poor wheel alignment
4-
Page 164 of 382
Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 163
SymptomCauseCorrective Action Reference
Loud or abnormal
noises From the
transmission
Insufficient
transmission oil
Add oilSee
Automatic
Transmission Fluid
0 251
Transmission inner
components faulty
4-
From differential Insufficient differential
gear oil
Add oilSee
Rear Axle
(Gear Oil Viscosity
Chart) 0271 or
Rear Axle (Oil
Level Check) 0272
Differential inner
components faulty
4-
From the
suspension Spring pins, shackles,
or stoppers worn
4-
From the driveshaft Poor lubrication in each
component
Lubricate themSee
Owner Checks
and Services 0340
Splines or bearings worn
4-
Page 165 of 382

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
164 Driving and Operating
Emergencies (Disabled
Vehicle)
When the Vehicle
Breaks Down
When the Vehicle Stops While
Driving
The brake booster will no longer
operate and brake effectiveness will
be reduced. If the engine cannot be
started, promptly have the vehicle
inspected and repaired.
If the engine stopped because the
vehicle ran out of fuel while driving,
refueling alone will not be enough to
restart the engine. Bleed the fuel
system after refueling the vehicle.
When the Fuel Tank is Empty
SeeRunning Out of Fuel 0233.
When the Engine Stalls and
Cannot Be Restarted
Move the selector lever to the "N"
position and push the vehicle to a
safe place.
{Warning
Vehicle operations will change, so
stop the vehicle in a safe place
with the following in mind.
The power steering system will
not work so the steering wheel
will be hard to turn. It will require
more strength than during normal
operation.
As the brake booster will no
longer be functional, brake
effectiveness will be greatly
reduced. Be sure to apply more
pressure than usual to the brake
pedal.
If the power assist steering
system goes out because the
engine has stopped or the assist
system has malfunctioned, the
vehicle can still be steered.
However, much greater effort is
needed, especially in sharp turns
or at low speeds.
You and others could be seriously
injured. When the Vehicle Breaks Down
During Driving
1. Use the hazard warning flasher any time to warn other drivers,
day or night, and pull the
vehicle immediately over to a
safe place that does not
impede traffic (shoulder). Place
triangle reflectors to alert other
traffic to the presence of your
vehicle.
2. If the vehicle can be exited safely, have the other
passengers get out and wait in
a safe place.
3. If the vehicle can be exited safely, walk to a safe place and
take appropriate measures by
using the closest
telephone, etc.
See Hazard Warning Flashers 094.
Page 166 of 382

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 165
If There is a Fuel Leak
{Danger
Leaking fuel from the vehicle is
dangerous due to possible
combustion or explosion. Stop the
engine immediately.
You and others could be seriously
injured or killed.
Starting and
Operating
New Vehicle Break-In
Good vehicle care begins with
proper break-in. While every new
vehicle goes through rigid factory
and dealer inspection and tests
before delivery, the care you give
your vehicle during the initial
break-in period can pay off in longer
life, better performance and more
economical operation.
It is therefore always recommended
that during the initial 1 000 km
(600 mile) break-in period, the
following few simple precautions are
carefully observed.
Follow the recommendations listed
below:
.Warm up the engine by driving
easily for the first few minutes
before placing it under load.
. Do not drive for extended
periods at any one constant
speed, either fast or slow, during
the first 800 km (500 miles). .
Use the correct gear to maintain
the desired road speed without
lugging the engine.
. Avoid racing the engine,
full-throttle starts and aggressive
application of brakes when
stopping.
. Keep tires properly inflated for
the load carried.
. Check lubricant levels in the
engine and transmission weekly.
. Keep speeds below 80 km/h
(50 MPH) for the first 800 km
(500 miles).
. Use the lowest gear ratio
available when starting a loaded
vehicle and when climbing
slopes to avoid lugging the
engine.
. It is recommended that the
engine speed is restricted to
2,300 r/min.
Page 167 of 382

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
166 Driving and Operating
Mechanical Driveshaft Brake
Burnish Procedure
It is recommended that the
driveshaft mounted parking brake
be burnished as part of the new
vehicle break-in procedure.
Increased parking brake
performance will result when the
parking brake is burnished as
specified below:
.Make 10 moderate stops, using
the hand brake, from 16 km/h
(10 MPH) while spacing the
stops a minimum of 4 km
(2.5 miles) apart.
. Operate the vehicle at 32 km/h
(20 MPH) between stops.Pedals
Sit in a correct driving position on
the seat and operate the brake
pedal (1) and accelerator pedal (2)
with your right foot. To avoid
accidentally pressing the wrong
pedal, check the pedal positions
and practice putting your foot on the
desired pedal.
{Warning
A can or bottle rolling on the floor
may prevent brake pedal
operation if it is caught under the
pedal. This is very dangerous.
A floor mat must be placed
correctly. An incorrectly installed
floor mat may hinder the free
movement of each pedal. You
and others could be seriously
injured.
Ignition Positions
Engine Control Switch
{Warning
While driving, never turn the
engine control switch to the
LOCK position. The key could be
removed from the switch, which
then locks the steering wheel.
This is extremely dangerous.
You and others could be seriously
injured.
Page 168 of 382

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 167
Caution
After starting the engine, do not
turn the engine control switch to
the START position. Otherwise,
the starter motor may be
damaged.
Using electrical devices such as
the audio system for an extended
time period with the engine
stopped can completely discharge
the battery.
The starting circuit, engine alarm
circuits and accessory circuits are
all controlled by the engine control
switch.
1 LOCK : Lock is in the position
fully counterclockwise. In this
position, the key can be inserted or
removed. To place the engine control switch in the LOCK position,
press and hold the key in the ACC
position and then turn it to the
LOCK position. If you will leave the
vehicle, remove the key and turn the
steering wheel until it locks. The
steering wheel will be locked to help
prevent theft.
2 ACC :
Accessory is in the first
position clockwise. In this position,
the audio and other accessories can
be used with the engine stopped.
3 ON : This ON position is in the
second position clockwise. The key
stays in this position while the
engine is running. Engine control,
warning circuits, gauge circuits, and
accessory circuits are energized.
The engine cylinder heaters or glow
plugs are also turned on when the
switch is in the ON position. The
wait-to-start light will come on and
stay on until the glow plugs are
heated enough. When this light
goes off, turn the switch to the
START position.