
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
254 Vehicle Care
Adding oil above the "Position A"
mark on the oil dipstick could result
in faulty engine operation. Be sure
to check the oil level by using the oil
dipstick.
Failure to use the recommended
engine oil could result in engine or
DPF breakdown, or in poor fuel
efficiency. Be sure to use the
recommended engine oil.
Choosing the Right Quality Oil
If you do not use the oil intended for
a vehicle equipped with a Diesel
Particulate Filter (DPF), both the
engine and the DPF may break
down and fuel economy may
decrease. Be sure, therefore, to use
the oil intended for vehicles
equipped with DPF.
GM recommends engine oil that
supports DPF (Low ash oil). Use of
engine oil that does not support low
ash will increase the PM produced
by engine combustion.
Consequently, the maintenance
interval of the DPF filter will be
reduced.Oil Identification Logo
A logo (symbol) is used on most oil
containers to help you select the oil
you should use. The top portion of
the logo shows the oil quality by API
designations such as CK4 or others.
The center portion of the logo
shows the SAE viscosity grade,
such as SAE *W-40 (* indicates
viscosity on the low temperature
side). You should look for this logo
on the oil container, and use ONLY
oil containing the logo.
Change Intervals
The oil and oil filter change intervals
for your engine are based on the
use of recommended oil quality and
viscosity, as well as high-quality
filters such as genuine GM oil filters.
Using oil other than recommended,
or oil and filter change intervals
longer than recommended, could
reduce engine life. Damage to
engines due to improper
maintenance or use of incorrect oil
quality and/or viscosity is not
covered by the new vehicle
warranty.
Your engine was filled with a
high-quality engine oil when it was
built. You do not have to change this
oil before the first recommended
change interval. Oil and filter
change intervals depend on how
you use your vehicle. For
information on the proper oil and
filter change intervals. See
Maintenance Schedule
0345.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
256 Vehicle Care
This Engine Oil Viscosity Grade
Chart shows general information.
For this vehicle, oil with *W-40
viscosity is recommended.
Changing the Engine Oil and
Oil Filter
Engine oil and the oil filter are
important factors in engine
performance and lifespan. Be sure
to use only the specified oil and oilfilters. The engine oil level must be
checked and the oil should be
changed regularly according to the
Maintenance Schedule.
Use the indicated oil quantities only
as guidelines when changing the
engine oil. After changing the oil,
make sure the oil is at the required
level. See
Capacities and
Specifications 0389. Failure to use the recommended
engine oil could result in engine or
DPF breakdown, or in poor fuel
efficiency. Be sure to use the
recommended engine oil.
Engine oil change precaution:
.
When adding oil, remove the
dipstick.
. After adding oil, wait for at least
5 minutes before starting the
engine. Be sure to reinstall the
dipstick.
Discarded Parts, Oils and
Other Liquids
When changing oils, filters, engine
coolant or other liquids, be sure to
have a container ready in advance
for their disposal.
Use methods conforming to legal
requirements for discarding or
disposing of parts, oils, filters or
engine coolant after change or
replacement.
Do not dispose of used engine oil,
fuel or any other oil in a careless
manner such as pouring it on the
ground, into sewers, or into streams

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 257
or bodies of water. Instead, recycle
it by taking it to a used oil collection
facility which may be found in your
community.
Engine Oil (Gasoline)
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
. Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
. Change the engine oil at the
appropriate time. See
Maintenance Schedule 0345.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Dipstick Access
Single Cab Model
1. Engine Oil Dipstick
2. Oil Filler Cap
Access to the engine oil dipstick is
located on the engine left side after
tilting the cab. Crew Cab Model
1. Strap
2. Seat Cushion
3. Catch Hooks

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 263
.Diesel Engine Dipstick H
(HOT) —Transmission fluid
temperature Approx. 70 -
80 °C (158 - 176 °F).
. For diesel engines, the “C
(COLD)” range on the
dipstick is a guide used by
your dealer for specialized
equipment used to replace
or service the automatic
transmission fluid. When
performing your own
inspections, always use the
“H (HOT)” range after
warming up the vehicle.
The fluid must be hot to
ensure an accurate check.
The fluid level rises as
temperature increases.
6. If the fluid level is too low, add the specified fluid through the
dipstick guide tube. Also, check
whether there are no fluid
leaks.
7. Insert the dipstick securely into position.{Warning
Be extremely careful not to burn
yourself when checking the oil
level if the engine temperature is
high. Protect yourself with
gloves etc.
You and others could be seriously
injured.
Discarded parts, oil, grease and
fluids could have an adverse effect
on the environment. It is difficult to
dispose of these, so have your
dealer handle all checks and
replacements.
Engine Air Cleaner/Filter
Air Cleaner
Use of clogged air cleaner element
not only causes a deterioration in
the engine output but also increased
fuel consumption and dark exhaust
smoke. Be sure to use a genuine air cleaner
element. If other air cleaner element
is used, it may cause the sensor to
output a wrong signal.
See
Maintenance Schedule 0345.
Air Cleaner Indicator Light
(Diesel Vehicles Only)
When the air cleaner indicator light
comes on, check the air cleaner
element. If the air cleaner element is
clogged, replace the air cleaner
element.
See Vehicle Messages (Diesel
Only) 097.
See Maintenance Schedule 0345.
Engine Coolant
Protection of Engine against
Overcooling
Overcooling of the engine not only
accelerates wear of the vital engine
parts but also hurts fuel economy.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
264 Vehicle Care
Engine Coolant in Cold
Weather
To prevent the engine damage due
to freezing of the engine coolant,
mix the coolant and water at the
ratio of 50/50.
Replace rubber hoses whenever
they crack or are damaged; even
minor cracks allow engine coolant
solution to leak.
{Warning
If your engine cooling system
overheats, seeEngine
Overheating 0269. Continued
operation of the engine even for a
short time may result in a fire and
the possibility of personal injury
and/or severe vehicle damage.
You and others could be seriously
injured.
Your vehicle has an engine coolant
recovery system, expansion bottle
and/or an engine coolant reserve
tank system. Engine coolant in the
system expands with heat and overflows into the reserve tank.
When the system cools, engine
coolant is drawn back into the
radiator.
The engine cooling system has
been filled at the factory with a
quality engine coolant. It is
important to use proper engine
coolant to prevent damage to
engine cooling system components.
The engine cooling system is
designed to use engine coolant
rather than plain water. See
Recommended Fluids and
Lubricants
0378.
See the Maintenance Schedule to
find out when the engine coolant
must be replaced. Note that
changing the engine coolant is
needed to replenish the rust
inhibitors to make certain that all
parts of the engine cooling system
work well.
{Warning
Check, replenish or change the
engine coolant only after the
engine has sufficiently
cooled down.
Do not loosen or remove the cap
of the radiator or engine coolant
reserve tank cap when the engine
coolant is still hot. Hot vapor or
boiling water may burst out and
cause a burn.
When removing the radiator cap
or engine coolant reserve tank
cap, use a thick cloth to cover the
cap and turn it slowly.
Engine coolant is toxic and must
not be ingested. If the engine
coolant is mistakenly ingested,
seek prompt medical attention.
If the engine coolant gets in your
eyes, rinse your eyes immediately
with a large amount of water for
15 minutes or longer. Also, if your (Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 273
Power Steering Fluid
The power steering fluid level must
be checked and it must be changed
according to the Maintenance
Schedule. SeeMaintenance
Schedule 0345.
When replenishing power steering
fluid or flushing the power steering
system, always use ATF
(Dexron
®-VI). Failure to use the
proper fluid may damage the power
steering system seals and hoses,
leading to fluid leakage.
Checking the Power Steering
Fluid Level
For the 3.0L diesel vehicles, the
fluid level is correct if it is between
the “MAX” and“MIN” lines on the
reserve tank. If the level is lower
that the “MIN”line, add fluid up to
the “MAX” line.
For the 5.2L diesel vehicles, the
fluid level is correct if it is between
the“MAX” and“MIN” lines on the
reserve tank. If the level is lower
that the “MIN”line, add fluid up to
the “MAX” line.
The reserve tank is located at the
rear of the engine compartment on
the right. When you have finished
checking the fluid level, securely
install the cap and cover.
For single cab gasoline vehicles, the
fluid level is correct if it is between
the "MAX" and "MIN" lines on the oil
dipstick. If the level is lower than the
"MIN" line, add fluid up to the
"MAX" line.
The reserve tank is located at the
front left side of the engine.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
276 Vehicle Care
Follow the recommendations for
brake checks in the Maintenance
Schedule.
GM replacement brake lining
material is recommended for this
vehicle to maintain the balance
between front and rear brake
performance. GM replacement
brake parts have been carefully
selected to provide the proper brake
balance for purposes of both
stopping distance and controllability
over the full range of operating
conditions. Installation of front or
rear brake lining material with
performance different from that of
the replacement parts
recommended for this vehicle can
change the intended brake balance
of this vehicle.
Checking the Brake Electric
Vacuum Pump (4500HD/
4500XD Series)
1. Turn the engine control switchto the "ON" position (do not
start the engine), and press the
brake pedal several times. 2. Check for the noisy sound of
the electric vacuum pump
inside the instrument panel at
the same time as vacuum
warning buzzer sound, and
check that the brake low
vacuum warning light
comes on.
3. Then, start the engine. The main vacuum pump driven by
the engine will start running.
If the electric vacuum pump
operation (noisy sound) and
the vacuum warning buzzer
stop, and the brake low
vacuum warning light goes off
thereafter, the operation is
normal.
4. If you cannot hear the noisy sound or the noisy sound stays
on all the time, have the
vehicle inspected by the
nearest dealer immediately.Hydraulic Brake Booster (HBB)
The 5500HD, 5500XD models are
equipped with a HBB system. HBB
is a brake booster device that utilizes hydraulic pressure from the
HBB pump integral with the power
steering pump.
If the brake booster warning light
comes on or a warning buzzer
continues to sound, there may be a
problem with the HBB.
If this warning light comes on while
driving, immediately stop your
vehicle at a safe place well clear of
traffic and promptly contact the
nearest dealer for inspection.
Hydraulic brake booster (HBB)
characteristics
In the 5500HD, 5500XD models, an
unusual sound from under the
instrument panel may be heard from
the hydraulic system while brakes
are used. It does not mean trouble.
It is not a sign of malfunction.
If you pump the brakes with the
engine off, a squeaking sound can
be heard. This comes from the
auxiliary accumulator. It is not a
malfunction. With the engine
running, a similar sound can be
heard during sudden braking.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
278 Vehicle Care
major brake problems. As such,
mixing of these two fluids can
ultimately lead to vehicle fire or
other serious accidents.
When the pump operates while the
engine is running, the fluid in the
hydro- booster will become hot.
During normal braking, the
temperature in piping and within
the hydro-booster can rise above
100 °C (212 °F). For this reason,
special care will be required when
working with hydro-booster
components. If the hydro- booster is
to be removed from the vehicle,
shut off the engine and then allow at
least 30 minutes for it to cool down
before beginning this operation.
Even when the engine is stopped,
the hydro-booster's accumulator will
remain in a highly-pressurized
condition for a significant period of
time. Before removing the
hydro-booster or piping from the
vehicle, stop the engine and
depress the brake pedal at least 10
times in order to lower the
accumulator pressure to
atmospheric pressure. This is of
particular importance whenremoving components such as the
accumulator or pressure switch from
the hydro-booster. If these
operations are attempted while the
accumulator is still at a high
pressure, hydro-booster fluid may
spray out.
Checking the Hydro-booster Fluid
Level
Check the hydro-booster fluid level
and change the fluid according to
the Maintenance Schedule.
The hydro-booster fluid level is
correct if it is between the "MAX"
and "MIN" lines. If the level is too
low, add fluid up to the "MAX" line.
Be sure to use ATF Dexron
®-VI fluid
when adding fluid. The brake
booster reservoir is located behind
the cab on the left side.
Brake Pedal
Stroke
Shut off the engine and press the
brake pedal about 10 times strongly,
then check the brake pedal for free
play by lightly pushing it by hand
until you feel resistance.
Free play (measured at the tip of pedal)
4 - 7 mm (0.16 - 0.28 in) (3500/4500)