Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16547501) - 2023 - CRC - 6/10/22
Driving and Operating 159
Maintenance when Trailer Towing
The vehicle needs service more often when
used to tow trailers. SeeMaintenance
Schedule 0242. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically that all nuts and bolts on
the trailer hitch are tight.
Engine Cooling when Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0186.
Trailer Towing
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle. Trailering is different than just driving the
vehicle by itself. Trailering means changes in
handling, acceleration, braking, durability,
and fuel economy. Successful, safe trailering
takes correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before pulling a
trailer.
Trailer Weight
{Warning
Never exceed the towing capacity for
your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades, outside
temperature, dimensions of the front of the
trailer, and how frequently the vehicle is
used to tow a trailer.
Trailering Weight Ratings
When towing a trailer, the combined weight
of the vehicle, vehicle contents, trailer, and
trailer contents must be below all of the
maximum weight ratings for the vehicle,
including:
.Gross Combined Weight Rating (GCWR)
.Gross Vehicle Weight Rating (GVWR)
.Maximum Trailer Weight Rating
.Gross Axle Weight Rating-Rear (GAWR-RR)
.Maximum Trailer Tongue Weight Rating
See “Weight-Distributing Hitch Adjustment”
under Towing Equipment 0167 to determine
if equalizer bars are required to obtain the
maximum trailer weight rating.
See “Trailer Brakes” underTowing
Equipment 0167 to determine if brakes are
required based on the trailer weight.
The only way to be sure the weight is not
exceeding any of these ratings is to weigh
the tow vehicle and trailer combination,
fully loaded for the trip, getting individual
weights for each of these items.
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16547501) - 2023 - CRC - 6/10/22
160 Driving and Operating
{Warning
You and others could be seriously injured
or killed if the trailer is too heavy or the
trailer brakes are inadequate for the load.
The vehicle may be damaged, and the
repairs would not be covered by the
vehicle warranty.
Only tow a trailer if all the steps in this
section have been followed. Ask your
dealer for advice and information about
towing a trailer.
Gross Combined Weight Rating (GCWR)
GCWR is the total allowable weight of the
completely loaded vehicle and trailer
including any fuel, passengers, cargo,
equipment, and accessories. Do not exceed
the GCWR for your vehicle. The GCWR for
the vehicle is on the Tow Rating Chart
following.
To check that the weight of the vehicle and
trailer are within the GCWR for the vehicle,
follow these steps:1. Start with the curb weight from the Tow Rating Chart.
2. Add the weight of the trailer loaded with cargo and ready for the trip. 3. Add the weight of all passengers.
4. Add the weight of all cargo in the
vehicle.
5. Add the weight of hitch hardware such as a draw bar, ball, load equalizer bars,
or sway bars.
6. Add the weight of any accessories or aftermarket equipment added to the
vehicle.
The resulting weight cannot exceed the
GCWR value shown on the Tow Rating
Chart.
The gross combined weight can also be
confirmed by weighing the truck and trailer
on a public scale. The truck and trailer
should be loaded for the trip with
passengers and cargo.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0126. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating is
calculated assuming only the driver is in the
tow vehicle and it has all the required
trailering equipment. The weight of
additional optional equipment, passengers,
and cargo in the tow vehicle must be
subtracted from the maximum trailer
weight.
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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170 Driving and Operating
Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended
side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning light
will flash on the instrument cluster. Reduce
vehicle speed by gradually removing your
foot from the accelerator. If trailer sway
continues, StabiliTrak/ESC can reduce engine
torque to help slow the vehicle. TSC will notfunction if StabiliTrak/ESC is turned off. See
Traction Control/Electronic Stability Control
0
142.
{Warning
Trailer sway can result in a crash and in
serious injury or death, even if the
vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing your
foot from the accelerator. Then pull over
to check the trailer and vehicle to help
correct possible causes, including an
improperly or overloaded trailer,
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment 0167 for trailer
ratings and hitch setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection. Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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188 Vehicle Care
If the decision is made not to lift the hood,
get service help right away.
Engine Fan
The vehicle has a clutched engine cooling
fan. When the clutch is engaged, the fan
spins faster to provide more air to cool the
engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is
not fully engaged. This improves fuel
economy and reduces fan noise. Under
heavy vehicle loading, trailer towing, and/or
high outside temperatures, the fan speed
increases as the clutch more fully engages,
so an increase in fan noise may be heard.
This is normal and should not be mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system
functioning properly. The fan will slow down
when additional cooling is not required and
the clutch partially disengages.
This fan noise may be heard when starting
the engine. It will go away as the fan clutch
partially disengages.
Power Steering Fluid
The power steering fluid reservoir is in the
engine compartment on the driver side of
the vehicle. SeeEngine Compartment
Overview 0176 for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless there is a leak
suspected in the system or an unusual noise
is heard. A fluid loss in this system could
indicate a problem. Have the system
inspected and repaired.
Wait for the power steering system to cool,
with the engine off, before checking the
fluid.
How to Check Power Steering Fluid
To check the power steering fluid:
1. Set the ignition off and let the engine compartment cool down. 2. Wipe the cap and the top of the
reservoir clean.
3. Unscrew the cap and wipe the dipstick with a clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the fluid level on the dipstick.
The level should be between the ADD and
FULL marks. If necessary, add only enough
fluid to bring the level up to the hashed
area between the ADD and FULL marks, do
not overfill.
To prevent contamination of brake fluid,
never check or fill the power steering
reservoir with the brake master cylinder
cover off.
What to Use
Caution
Use of the incorrect fluid may damage
the vehicle and the damages may not be
covered by the vehicle warranty. Always
use the correct fluid listed in
Recommended Fluids and Lubricants
0246.
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 199
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
1 ABS Motor Fuses Usage
2 ABS Module Fuses Usage
3 Right Trailer Stoplamp/ Turn Signal Lamp
4 –
5 –
6 Fuel System Control Module/Ignition
7 Body Control Module 5
8 Body Control Module 7
9 Body Control Module 4
10 Instrument Cluster 11 Trailer Wiring
12 –
13 Interior Rear Vision Camera Module
14 Windshield Washer
16 Horn 17 Transmission
18 A/C
19 Engine Control Module Battery
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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200 Vehicle Care
FusesUsage
20 Left Stop/Turn Cutaway Lamp
21 Left Stop/Turn Trailer Lamp
22 Right Stop/Turn Cutaway Lamp
23 –
24 Fuel Pump 25 Auxiliary Power Outlet
26 Body Control Module 3 27 Special Equipment Option
28 Airbag
29 Steering Wheel Sensor
30 Engine Control Module Ignition
31 Transmission Control Module Ignition
32 Transmission Control Module 1 Battery
33 Rear Parking Aid Module Fuses
Usage
34 –
35 –
36 Fuel System Control Module Battery
41 Transmission Control Module 2/Battery Power
42 Trailer Wiring
43 –
44 Starter Solenoid 45 Engine Control Module/ Powertrain Signal 2
46 DC-AC Inverter 47 Fan Low Speed 51 Left High-Beam Headlamp
52 Right High-Beam Headlamp
53 Left Low-Beam Headlamp
54 Right Low-Beam Headlamp
55 Wipers Fuses
Usage
56 Canister Vent Solenoid
58 Body Control Module 2
59 Body Control Module 1 61 Engine Oil Solenoid
62 O2 Sensor 2
63 –
64 Mass Airflow/ Canister Vent
65 Ignition Coils/Injectors –Odd
66 Daytime Running Lamps 2
67 Daytime Running Lamps 1
68 Auxiliary Stoplamps
69 External Power for Trailer
70 Upfitter Stoplamps 71 Fuel Heater/FlexFuel Sensor
72 Body Control Module 6
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 201
FusesUsage
73 Lighter/Data Link Connector
74 Front Blower 75 Engine Control Module
76 –
77 O2 Sensor 1
78 Engine Control Module/ Powertrain Signal 1
79 Ignition Coils/Injectors –Even Relays
Usage
15 Run/Crank
37 –
38 Fuel Pump
39 Crank
40 A/C Compressor 48 –
49 Powertrain 50 –
57 –
60 – Auxiliary Fuse Block
This component is near the fuse block in the
engine compartment
Fuses Usage
MR-1 Upfitter 1
MR-2 Upfitter 2
MR-3 Upfitter Power Control
Relays Usage
MR Rel 1 Upfitter 1
MR Rel 2 Upfitter 2
Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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208 Vehicle Care
Treadwear Indicators:Narrow bands,
sometimes called wear bars, that show
across the tread of a tire when only
1.6 mm (1/16 in) of tread remains. See
When It Is Time for New Tires 0214.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system
that provides consumers with ratings
for a tire's traction, temperature, and
treadwear. Ratings are determined by
tire manufacturers using government
testing procedures. The ratings are
molded into the sidewall of the tire.
See Uniform Tire Quality Grading 0216.
Vehicle Capacity Weight
:The number
of designated seating positions
multiplied by 68 kg (150 lbs) plus the
rated cargo load. See Vehicle Load
Limits 0126.
Vehicle Maximum Load on the Tire
:
Load on an individual tire due to curb
weight, accessory weight, occupant
weight, and cargo weight. Vehicle Placard
:A label permanently
attached to a vehicle showing the
vehicle's capacity weight and the
original equipment tire size and
recommended inflation pressure. See
“Tire and Loading Information Label”
under Vehicle Load Limits 0126.
Tire Pressure
Tires need the correct amount of air
pressure to operate effectively.
{Warning
Neither tire underinflation nor
overinflation is good. Underinflated
tires, or tires that do not have
enough air, can result in:
.Tire overloading and overheating,
which could lead to a blowout
.Premature or irregular wear
.Poor handling
.Reduced fuel economy for
internal combustion engine
vehicles
(Continued)
Warning (Continued)
.Reduced range for electric vehicles
Overinflated tires, or tires that have
too much air, can result in:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from road
hazards
The Tire and Loading Information label
on the vehicle indicates the original
equipment tires and the correct cold
tire inflation pressures. The
recommended pressure is the minimum
air pressure needed to support the
vehicle's maximum load carrying
capacity.
For additional information regarding
how much weight the vehicle can carry,
and an example of the Tire and Loading
Information label, see Vehicle Load
Limits 0126. How the vehicle is loaded
affects vehicle handling and ride