maintenance CHEVROLET LOW CAB FORWARD 2020 Service Manual

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
318 Service and Maintenance
training of dealer technicians
throughout the country and is
supported with a continuous
follow-up of publications and other
service information. The use of
genuine parts and accessories,
which have the same high quality
standards as original equipment
parts, and the use of factory
approved tools developed and
tested for use by the authorized
dealer also contribute to the high
quality of service.
If you have any questions on how to
keep your truck or chassis in good
condition, see your authorized
dealer, the place many truck owners
choose to have their maintenance
work done. Your authorized dealer
can be relied upon to use proper
parts and practices.
Some of these services can be
complex, so unless you are
technically qualified and have the
necessary equipment, you should
let your authorized dealer's service
department or another qualified
service center do these jobs.The schedule includes general
maintenance which you or a
qualified technician should perform
periodically.
Explanation of Vehicle
Maintenance and Log
The following is a brief explanation
of normal vehicle use.
NORMAL VEHICLE USE—The
maintenance instructions contained
in this section are based on the
assumption that your vehicle will be
used as designed:
.
To carry passengers and cargo
with the limitations indicated on
the vehicle VIN and GVW plate.
. On reasonable road surfaces
within legal operating limits.
. On a daily basis, as a general
rule, for at least several miles/
kilometers.
Unusual operating conditions, such
as driving in dusty areas (sweeper,
agricultural or off-road vehicles),
extended idling (refrigeration vehicles), or vehicles operated for
frequent short trips, will require
more frequent vehicle maintenance.
The log groups items according to
mile/kilometer service intervals. Use
the item codes (letter and number)
to find the description of the
maintenance and the time intervals.
Follow whichever interval comes
first, time or miles/kilometers.
After the maintenance services are
performed, insert the month, day
and mileage/ kilometers in the area
provided next to the serviced item.
The services shown up to
176 000 km (110,000 miles) are to
be repeated after the initial
176 000 km (110,000 miles) at the
same intervals.
Severe Driving Conditions
A vehicle operated under severe
conditions (see list below) requires
more frequent maintenance.
.
Frequent short trips of less than
6 kilometers (4 miles) in
moderate temperatures

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 319
.Frequent short trips of less than
16 kilometers (10 miles) in sub-
freezing temperatures
. Frequent and extended low-
speed engine operation (door-
to- door deliveries, stop- and- go
traffic, etc.)
. Driving on unpaved roads with
heavy dust
. Towing a trailer
Power Take Off (PTO) and
Extended Idle Use
When the vehicle is used with the
PTO equipment or used in a way
that requires extended idle time,
one hour of use shall be deemed
the same as 33 miles. See Driver
Information Center (DIC) 070 for
hourmeter.
Preventive Maintenance
As any mechanical device operates,
a certain amount of wear occurs.
The amount of wear depends on
certain variables –type and method
of operation and the schedule of
maintenance. These variables may be emphasized as critical to
malfunction but each is dependent
upon the other. For example, if a
vehicle is repeatedly overloaded,
driven at excessive speed or
improperly shifted, no schedule of
maintenance can prevent
malfunction. Also, if a preventive
maintenance schedule is not
followed, or is improperly carried
out, no amount of correct vehicle
operation will prevent malfunction.
If vehicle application, operation and
preventive maintenance schedules
and procedures are followed and
properly carried out, the life of the
vehicle will be greatly extended.
For example, regular attention to the
engine oil is essential. The oil level
must be periodically checked and oil
added whenever needed. Also, the
oil should be changed at the
intervals specified with the proper
quality and viscosity of oil. If your
engine should run excessively low
on oil or if the oil has lost its
lubricating qualities because of old
age, serious engine damage could
occur.
Maintenance Schedule Table
Letters Used to Indicate
Maintenance Service Types
I :
Inspect then clean, repair or
replace as necessary
A : Adjust
R : Replace
T : Tighten to the specified torque
L : Lubricate
C : Clean

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
320 Service and Maintenance
No. Service Interval16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
1 Engine noise check I - I I I - I I I - I I I - I
2 Valve lash - - - A - - - A - - - A - - - or every
12 months
3 Engine oil and oil filter (2) R - R R R - R R R - R R R - R or every
12 months
4 Fuel filter - R - R - R - R - R - R - R - or every
24 months
5 Pre-fuel filter/water
separator
- R - R - R - R - R - R - R - or every
24 months
6 Air cleaner filter - - - - - - - - - - - - - - - indicator (3)
7 Damage to air intake
ducts and hoses - I - I - I - I - I - I - I - or every
12 months
8 Drive belts I - I I I - I I I - I I I - I or every
12 months
9 Engine bolt torques - - - - - - I - - - - - I - -
10 Rotate tires Every 10 400 km (6,500 miles)

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 321
No. Service Interval16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
11 Engine cooling system I - I I I - I I I - I I I - I or every
12 months
12 Engine coolant Every 12 months: I
Every 24 months: R (when dealer recommended coolant is used)
13 Exhaust system I - I I I - I I I - I I I - I
14 DPF (clean filter) - - - - - - - - - - - - C - - or every
3,000 hours
15 DPF (pressure difference
sensor 0 point
adjustment) - - - - - - - - - - - - A - -
or every
3,000 hours
16 DPF (pressure difference
sensor hose) Every 160 000 km (100,000 miles): I
Every 400 000 km (250,000 miles): R or every
3,000 hours: I
17 Fuel line system I - I I I - I I I - I I I - I or every
12 months
18 Brake lining and pad
for wear I - I I I - I I I - I I I - I

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
322 Service and Maintenance
No. Service Interval16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
19 Brake drum and rotor for
wear and damage
- - I - I - - I - - I - I - I or every
12 months
20 Brake electric
vacuum pump I - I I I - I I I - I I I - I or every
12 months
21 Brake fluid I - I R I - I R I - I R I - I or every
12 months: I
or every
12 months: R
22 Hydraulic brake booster
(HBB) fluid (5500HD
5500XD models) - - - R - - - R - - - R - - -
or every
24 months
23 Brake line and hoses - - I - I - - I - - I - I - I or every
12 months
24 Parking brake cable I - I I I - I I I - I I I - I or every
12 months
25 Automatic transmission
fluid I - I R I - I R I - I R I - I
or every
12 months

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 323
No. Service Interval16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
26 Differential gear oil I - I R I - I R I - I R I - I or every
24 months
27 Power steering fluid - - - R - - - R - - - R - - - or every
24 months
28 Power steering oil hoses - - - - - - R - - - - - R - - or every
24 months
29 Steering wheel free
play (4) Every 10 400 km (6,500 miles): I
30 Steering gear box torque - - T - T - - T - - T - T - - or every
12 months
31 Drive shaft flange torque T - T T T - T T T - T T T - T or every
12 months
32 Drive shaft lubrication L - L L L - L L L - L L L - L or every
12 months
33 Leaf spring U-bolt
torque (4) T - T T T - T T T - T T T - T

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
324 Service and Maintenance
No. Service Interval16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
34 Wheel nut torque (4) Every 10 400 km (6,500 miles)
35 King pin L - L L L - L L L - L L L - L or every
12 months
36 Wheel hub bearing grease
- Front (5) - - - R - - - R - - - R - - - or every
24 months
37 Air conditioner blower
filter Cleaned once a month
38 Exhaust injector Cleaned every 176,000 km (110,000 miles)
39 DEF supply pump filter
element Every 192 000 km (120,000 miles): R or every
24 months
40 Starter When the starter indicator light (amber) comes on: R
41 Windshield wiper blades Replace every 12 months
Remarks
(1) In case this column is blank,
follow kilometers (miles). (2)
Use of oils other than CK-4 may
require shorter maintenance
intervals and may cause
nonconformity to regulations. (CJ-4 can be used while it is available.)
Use of oils with other viscosity than
*W-40 may also require shorter

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 325
maintenance intervals and may
cause a problem with engine
durability.
(3)Refer to "Air Cleaner Indicator
Light" under Engine Air Cleaner/
Filter 0243.
(4) Initial check at 1 040 km
(650 miles) is required.
(5) Be sure to discard used grease
seal, and always use new grease
seal for installation.
Explanation of Complete
Vehicle Maintenance Schedule
The following is a brief explanation
of each of the services listed in the
preceding Complete Vehicle
Maintenance Schedule.
1. Engine Noise : These
components have an effect on the
control of noise emissions. Service Interval Maintenance procedure
Engine
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
Cooling System
Every 16 000 km (10,000 miles) Inspect fan, shroud and radiator for
attachment, tears or cleanliness.
Replace as necessary.
Air intake system
Every 24 000 km (1,500 miles) Inspect all ducts, hoses and intake
silencers for leaks or chafing. Repair or
replace as necessary.
Exhaust system
Every 16 000 km (10,000 miles) Inspect silencer, pipes, gaskets, clamps
and mounting for exhaust gas leaks or
looseness. Repair or replace as
necessary.
Cab
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
2. Valve Lash : Incorrect valve
clearance will result in increased
engine noise and lower engine
output, thereby adversely affecting
engine performance. Retorque rocker shaft bracket nuts before
checking and adjusting valve
clearance.
Check and adjust valve clearance
every 80 000 km (50,000 miles) or
12 months whichever occurs first.

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
326 Service and Maintenance
3. Engine Oil and Oil Filter :
Change at interval noted below
depending upon driving conditions.
•Normal Service —Change every
16 000 km (10,000 miles) or
12 months whichever occurs first.
• Severe Service —Change every
8 000 km (5,000 miles) or 3 months
if you often drive under one or more
of these conditions: (a) driving in
dusty areas, (b) frequent idling or
idling for long periods, (c) driving
6 km (4 miles) or less in freezing
weather, or other short trips in cold
weather, where the engine does not
thoroughly warm up.
Change oil and filter as soon as you
can after driving in a dust storm.
When recommended oil is used, it
conforms to this maintenance
schedule. (Recommended oil: CK-4
(API designations))
4. Fuel Filter : Replace the fuel
filter every 24 000 km (15,000 miles)
or more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped). 5. Pre-Fuel Filter/Water
separator :
Replace the fuel filter
every 24 000 km (15,000 miles) or
more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped).
6. Air Cleaner Filter : The level of
dirt in the air cleaner element can
be checked against the indicator.
Replace the air cleaner filter when
the Driver Information Center (DIC)
shows "CHECK AIR FILTER".
7. Damage to Air Intake Ducts and
Hoses : Check for damage of air
intake ducts and hoses and that
those are correctly installed every
24 000 km (15,000 miles) or
12 months. Replace or adjust those
if necessary.
8. Drive Belts : Check belt driving
the fan, alternator or A/C
compressor every 16 000 km
(10,000 miles). Look for cracks,
fraying, wear, and proper tension.
9. Engine Bolt Torques : Loosened
bolts result in lower engine output.
Check and adjust manifold mounting, and injectors to correct
torque every 80 000 km
(50,000 miles).
10. Rotate Tires :
To equalize wear,
rotate tires and adjust tire pressures
every 10 400 km (6,500 miles). See
Tire Rotation 0297.
11. Engine Cooling System : At
12 months or 16 000 km
(10,000 miles) intervals, wash
radiator cap and filler neck with
clean water, pressure test system
and radiator cap for proper pressure
holding capacity, tighten hose
clamps and inspect condition of all
cooling and heater hoses. Replace
hoses if cracked, swollen or
otherwise deteriorated. Have the
hoses replaced by your authorized
dealer.
12. Engine Coolant : Inspect the
engine coolant every 12 months.
Replace the engine coolant every
24 months, drain the engine coolant
by opening the drain plug at the
bottom of the radiator core, flush
and refill the engine cooling system
with a new engine coolant. Refer to
"Preparing Engine Coolant" in

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 327
Engine Coolant0243. Have the
Engine Coolant replaced by your
authorized dealer.
13. Exhaust System : Check the
complete exhaust system every
16 000 km (10,000 miles). Check
body areas near the exhaust
system. Look for broken, damaged,
missing, or out-of-position parts.
Also inspect for open seams, holes,
loose connections, or other
conditions which could cause heat
build-up at the rear body floor pan,
or could let exhaust fumes seep into
the passenger compartment. Dust
or water in the cabin may indicate a
leak in that area. Required repairs
should be made at once.
14. DPF (Clean Filter) : Clean the
filter every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first.
15. DPF (Pressure Difference
Sensor 0 Point Adjustment) :
Adjust the sensor every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first. 16. DPF (Pressure Difference
Sensor Hose) :
Inspect the sensor
hose every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first. Replace the
sensor hose every 400 000 km
(250,000 miles).
17. Fuel Line System : Inspect the
fuel tank, cap and lines for damage
which could cause leakage every
16 000 km (10,000 miles). Inspect
fuel cap for correct sealing ability
and indications of physical damage.
Replace any damaged or
malfunctioning parts.
18. Brake Lining and Pad for
Wear : Check drum brake lining and
disc brake pad for wear or cracks
every 16 000 km (10,000 miles).
Check brakes (including parking
brake) more often if operating
conditions or driving habits result in
frequent braking.
Front disc brakes have built-in wear
noise indicators which are designed
to make a high pitched squeal or
cricket-like warning sound when the
brake pads are worn to the point
where new pads are needed. When the truck is in motion, the
sound may be constant or it may
come and go. Pressing the brake
pedal firmly may cause the sound
to stop.
Have the brake linings or the brake
pads replaced by your authorized
dealer as soon as possible after the
warning first becomes evident.
Failure to do so can result in
expensive damage to the brake
system or a serious crash.
19. Brake Drum and Rotor for
Wear and Damage :
Check brake
drums (rear and parking) and rotors
(front) for wear or damage every
32 000 km (20,000 miles) or
12 months whichever occurs first.
20. Brake Electric Vacuum Pump
(4500HD, 4500XD models) :
Inspect the brake electric vacuum
pump operation every 16 000 km
(10,000 miles) or 12 months,
whichever occurs first.