2003 GMC SONOMA weight

Vehicle* Axle RatioMaximum Trailer
WeightGCWR**
4WD Extended Cab
4.3L V6/Manual Trans. 3.42 4,000 lbs (1 816 kg) 8,000 lbs. (3 629 kg)
4.3 L V6/Manual Trans. 3.73 4,200 lbs. (1 907 kg) 8,500 lbs. (3 856 kg)
4.3 L Auto. Trans.3.42
3.735,500 lbs. (2 497 kg)
5,500 lbs. (2 497 kg)9,500 lbs. (4 309 kg)
4.3 L Auto Trans. w/ZR2 3.73 4,700 lbs. (2 132 kg) 9.000 lbs. (4 082 kg)
4WD Crew Cab
®
4.3L V6/Auto. Trans.3.42
3.735,200 lbs. (2 361 kg)
5,200 lbs. (2 361 kg)9,500 lbs. (4 309 kg)
9,500 lbs. (4 309 kg)
* If your vehicle is equipped with RPO V4A (Xtreme™
Sport Appearance Package), your vehicle was
neither intended nor designed to tow a trailer. For more
information on RPO codes, seeService Parts
Identification Label on page 5-88.
Maximum trailer weight 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.
The weight of the trailer tongue also affects trailering
capacity. See″Weight of the Trailer Tongue″next.**The Gross Combination Weight Rating (GCWR) is the
total allowable weight of the completely loaded vehicle
and trailer including any passengers, cargo, equipment
and conversions. The GCWR for your vehicle should
not be exceeded.
You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in your
Warranty and Owner Assistance Information Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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2003 - Sonoma OM

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. And if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle will be
carrying that weight, too. SeeLoading Your Vehicle
on page 4-46for more information about your vehicle’s
maximum load capacity.If you’re using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
After you’ve loaded your trailer, weigh the trailer and then
the tongue, separately, to see if the weights are proper.
If they aren’t, you may be able to get them right simply by
moving some items around in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper limit
for cold tires. You’llnd these numbers on the
Certication label at the rear edge of the driver’s door
above the door latch, or seeLoading Your Vehicle
on page 4-46. Then be sure you don’t go over the
GVW limit for your vehicle, including the weight of the
trailer tongue.
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2003 - Sonoma OM

Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you’ll need the right hitch. Here
are some rules to follow:
If you use a step-bumper hitch, your bumper could
be damaged in sharp turns. Make sure you have
ample room when turning to avoid contact between
the trailer and the bumper.
If you’ll be pulling a trailer that, when loaded, will
weigh more than 3,500 lbs. (1 589 kg) be sure to
use a properly mounted, weight-distributing
hitch and sway control of the proper size. This
equipment is very important for proper vehicle
loading and good handling when you’re driving.
If your vehicle has the bumper delete option, do not
bolt any type of hitch to the close-out panel. The
close-out panel will not support a hitch.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the
tongue of the trailer to help prevent the tongue from
contacting the road if it becomes separated from
the hitch. Instructions about safety chains may be
provided by the hitch manufacturer or by the trailer
manufacturer. For trailers up to 3,500 lbs. (1 589 kg) you
may attach the safety chains to the attaching points
on the bumper. For heavier trailers, follow the trailer or
hitch manufacturer’s recommendation for attaching
safety chains. Always leave just enough slack so you
can turn with your rig. Never allow safety chains to drag
on the ground.
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2003 - Sonoma OM

Trailer Brakes
If your trailer weighs more than 1,000 lbs. (450 kg)
loaded, then it needs its own brake–and they must be
adequate. Be sure to read and follow the instructions for
the trailer brakes so you’ll be able to install, adjust
and maintain them properly.
Your trailer’s brake system can tap into the vehicle’s
hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) ofuid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, then make the brake
uid tap at the port on the master cylinder that
sendsuid to the rear brakes. But don’t use copper
tubing for this. If you do, it will bend andnally break off.
Use steel brake tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be
sure the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
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Top Strap Anchor Location...............................1-43
Torque Lock...................................................2-35
Total Weight on Your Vehicle’s Tires..................4-55
Towing
Recreational Vehicle.....................................4-42
Towing a Trailer..........................................4-51
Your Vehicle...............................................4-42
Trailer
Recommendations.......................................4-50
Trailer Brakes.................................................4-57
Transfer Case................................................5-48
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection.......................6-32
Transmission
Fluid, Automatic...........................................5-20
Fluid, Manual..............................................5-23
Up-Shift Light..............................................3-27
Transmission Operation, Automatic....................2-25
Transmission Operation, Manual........................2-28
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-10
Transportation Options...................................... 7-7
Traveling to Remote Areas...............................4-15
Trip Odometer................................................3-23
Truck-Camper Loading Information....................4-48
Turn and Lane-Change Signals.......................... 3-5
Turn Signal/Multifunction Lever........................... 3-5
Turn Signals When Towing a Trailer..................4-58
Two-Piece Composite Headlamp System............5-51
Two-Tiered Loading.........................................4-48U
Underbody Flushing Service.............................6-30
Understanding Radio Reception........................3-67
Uniform Tire Quality Grading
............................5-63
United States
................................................... 7-4
Up-Shift Light
.........................................2-29, 3-27
Used Replacement Wheels
..............................5-66
Using Cleaner on Fabric
..................................5-80
Using RDS
....................................3-42, 3-50, 3-59
Using Song List Mode
.....................................3-65
Using the Recovery Hooks
...............................4-41
V
Vehicle
Control
........................................................ 4-5
Damage Warnings
........................................... iv
Loading
......................................................4-46
Parking Your
...............................................2-36
Symbols
......................................................... iv
Vehicle Identification
Number (VIN)
.............................................5-87
Service Parts Identification Label
...................5-88
Vehicle Personalization
Memory Seat
..............................................2-54
Vehicle Storage
..............................................5-42
Ventilation Adjustment
......................................3-19
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Vinyl.............................................................5-80
Visors...........................................................2-16
Voltmeter Gage..............................................3-26
W
Warning Lights, Gages and Indicators................3-20
Warnings
Hazard Warning Flashers............................... 3-3
Other Warning Devices.................................. 3-4
Safety and Symbols......................................... iii
Vehicle Damage.............................................. iv
Washing Your Vehicle......................................5-82
Weatherstrip Lubrication...................................6-27
Weight of the Trailer........................................4-53
Weight of the Trailer Tongue.............................4-55
What Kind of Engine Oil to Use........................5-14
What to Add ..................................................5-40
What to Do with Used Oil ................................5-17
What to Use ..........................5-26, 5-38, 5-47, 5-49
Wheels
Alignment and Tire Balance..........................5-64
Replacement...............................................5-65
When to Add Engine Oil..................................5-13
When to Change Engine Oil.............................5-16
When to Check......................................5-23, 5-59
When to Check and Change............................5-20
When to Check and Change Lubricant.......5-47, 5-49When to Check and What to Use.....................5-24
When to Check Power Steering Fluid................5-37
When to Inspect the Engine Air Cleaner/Filter.....5-19
When You Are Ready to Leave
After Parking on a Hill..................................4-60
Where to Put the Restraint.......................1-39, 1-40
Why Safety Belts Work....................................1-12
Window Lockout.............................................2-15
Windows.......................................................2-14
Manual......................................................2-15
Power ........................................................2-15
Sliding Rear................................................2-16
Swing-Out Windows.....................................2-16
Windshield and Wiper Blades...........................5-84
Windshield Washer........................................... 3-7
Fluid..........................................................5-38
Windshield Washer Fluid Level Check................6-26
Windshield Wiper
Blade Replacement......................................5-56
Fuses........................................................5-88
Windshield Wipers............................................ 3-7
Winter Driving................................................4-36
Wiper Blade Check.........................................6-27
Wood Panels.................................................5-81
Y
Your Vehicle and the Environment....................... 6-2
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2003 - Sonoma OM