2004 GMC ENVOY XL Owners Manual

Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dinghy towed if you
follow the proper procedures. The transmission has
no provisions for internal lubrication while being towed,
so it is important that you follow all the steps listed
in this manual to dinghy tow your four-wheel-drive
vehicle.
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to
the tow vehicle.{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle
to roll even if the transmission is in Park (P).
You or others could be injured. Make sure the
parking brake is rmly set before you shift the
transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL (N).
SeeFour-Wheel Drive on page 2-26for the
proper procedure to select the NEUTRAL
position for your vehicle.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
7. Turn the ignition off and leave the steering column
unlocked.
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Dolly Towing
Two-Wheel-Drive Vehicles
Two-wheel-drive vehicles should not be dolly towed.
Two-wheel-drive transmissions have no provisions
for internal lubrication while being towed. To properly
tow these vehicles, they should be placed on a platform
trailer with all four wheels off the ground.
Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dolly towed with
the rear wheels on the ground.
Use the following procedure to tow your vehicle:
1. Drive the vehicle onto the tow dolly.
2. Shift the automatic transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed
to the dolly.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle
to roll even if the transmission is in Park (P).
You or others could be injured. Make sure
the parking brake is rmly set before you shift
the transfer case to NEUTRAL.
6. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-26for the proper
procedure to select the NEUTRAL position for
your vehicle.
7. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
8. Turn the ignition off and lock the steering column.
4-48

Loading Your Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the vehicle
capacity weight and includes the weight of all occupants,
cargo and all nonfactory-installed options. Two labels
on your vehicle show how much weight it may properly
carry, the Tire and Loading Information label and the
Certication/Tire label.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose
control and crash. Also, overloading can
shorten the life of your vehicle.
Tire and Loading Information Label
A. Vehicle Capacity Weight
The Tire and Loading Information label is attached to
the center pillar, near the driver’s door latch. Vehicles
without a center pillar will have the Tire and Loading
Information label attached to the driver’s door edge.
This label lists the number of people that can be in your
vehicle and the total weight it can carry. This weight
is called the vehicle capacity weight.
4-49

The Tire and Loading Information label also tells you
the size and recommended ination pressure for
the original equipment tires on your vehicle. For more
information on tires and ination seeTires on page 5-55
andInation - Tire Pressure on page 5-64.
If your vehicle does not have the Tire and Loading
Information label, the Certication/Tire label shows the
tire size and recommended ination pressures needed to
obtain the Gross Vehicle Weight Rating (GVWR) and the
Gross Axle Weight Rating (GAWR) for the front and rear
axles. See “Certication/Tire Label” later in this section.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined weight of
occupants and cargo should never exceed
XXX pounds” on your vehicle placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and
passengers from XXX kilograms or XXX pounds.4. The resulting gure equals the available amount of
cargo and luggage load capacity. For example,
if the “XXX” amount equals 1400 lbs. and there will
be ve 150 lb. passengers in your vehicle, the
amount of available cargo and luggage load capacity
is 650 lbs. (1400−750 (5 x 150) = 650 lbs.).
5. Determine the combined weight of luggage and
cargo being loaded on the vehicle. That weight
may not safely exceed the available cargo
and luggage load capacity calculated in Step 4.
6. If your vehicle will be towing a trailer, the load from
your trailer will be transferred to your vehicle.
Consult this manual to determine how this reduces
the available cargo and luggage load capacity of
your vehicle.
SeeTowing a Trailer on page 4-55for important
information on towing a trailer, towing safety rules
and trailering tips.
4-50

Loading Your Vehicle
Item Description Total
AVehicle Capacity
Weight for Example 1=1,000 lbs (453 kg)
BSubtract Occupant
Weight 150 lbs
(68 kg)×2=300 lbs (136 kg)
CAvailable Occupant
and Cargo Weight =700 lbs. (317 kg)
Loading Your Vehicle
Item Description Total
AVehicle Capacity
Weight for Example 2=1,000 lbs (453 kg)
BSubtract Occupant
Weight 150 lbs
(68 kg)×5=750 lbs (340 kg)
CAvailable Cargo
Weight =250 lbs. (113 kg) Example 1
Example 2
4-51

Loading Your Vehicle
Item Description Total
AVehicle Capacity
Weight for Example 3=1,000 lbs (453 kg)
BSubtract Occupant
Weight 200 lbs
(91 kg)×5=1,000 lbs (453 kg)
CAvailable Cargo
Weight =0 lbs (0 kg)
Refer to your vehicle’s tire and loading information label
for specic information about your vehicle’s capacity
weight and seating positions. The combined weight of the
driver, passengers and cargo should never exceed your
vehicle’s capacity weight.
Certication/Tire Label
The Certication/Tire label is found on the driver’s door
edge, above the door latch. The label shows the size of
your original tires and the ination pressures needed to
obtain the gross weight capacity of your vehicle. This is
called the Gross Vehicle Weight Rating (GVWR). The
GVWR includes the weight of the vehicle, all occupants,
fuel, cargo and trailer tongue weight, if pulling a trailer.
The Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR). To nd out the actual loads on
your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help you
with this. Be sure to spread out your load equally on both
sides of the centerline. Example 3
4-52

Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
If you do have a heavy load, you should spread it out.
Similar appearing vehicles may have different GVWRs
and payloads. Please note your vehicle’s
Certication/Tire label or consult your dealer for
additional details.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose
control and crash. Also, overloading can
shorten the life of your vehicle.
Using heavier suspension components to get added
durability might not change your vehicle’s weight
ratings. Ask your dealer to help you load your vehicle
the right way.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.If you put things inside your vehicle-like suitcases, tools,
packages, or anything else-they will go as fast as the
vehicle goes. If you have to stop or turn quickly, or
if there’s a crash, they’ll keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn,
or in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There’s also important loading information for off-road
driving in this manual.
4-53

Electronically Controlled Air
Suspension System
Your vehicle may be equipped with an electronically
controlled air suspension system that automatically
keeps your vehicle level as you load and unload. The
system includes a compressor, two height sensors
and two air springs supporting the rear axle.
The system also has an internal clock to prevent
overheating. If the system overheats, all leveling function
stops until the system cools down. During this time,
the indicator light on the air inator system will be
ashing.
The ignition has to be on for the system to inate, in
order to raise the vehicle to the standard ride height
after loading. The system can lower the vehicle to the
standard ride height after unloading with the ignition
on and also for up to 30 minutes after the ignition has
been turned off.
You may hear the compressor operating when you load
your vehicle, and periodically as the system adjusts
the vehicle to the standard ride height.Load leveling will not function normally with the inator
hose attached to the inator outlet. Remove the inator
hose from the outlet during loading and unloading.
If the vehicle is parked for an extended period of time,
some bleed down of the suspension is normal. Upon
starting the vehicle, proper height will be achieved.
Overload Protection
The air suspension system is equipped with overload
protection. Overload protection is designed to protect
the air suspension system, and it is an indicator
to the driver that the vehicle is overloaded. When the
overload protection mode is on, it will not allow damage
to the air compressor. However, do not overload the
vehicle. SeeLoading Your Vehicle on page 4-49.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is activated,
the compressor operates for about 30 seconds to one
minute without raising the vehicle depending on the
amount of overload. This will continue each time
the ignition is turned on until the rear axle load is
reduced below GAWR.
4-54