1998 GMC ENVOY tow

Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much
your vehicle is used to pull a
trailer are all important. And,
it can also depend on any
special equipment that you have
on your vehicle.
The trailer should never weigh more than
5,000 lbs.
(2 268 kg). But even that can be too heavy.
Maximum trailer weight is calculated assuming the
driver and one passenger are
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.
You can ask your dealer for OUT 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 1908 Colonel Sam Drive
Oshawa, Ontario
LlH 8P7
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, See “Loading
Your Vehicle”
in the Index for more information about
your vehicle’s maximum load capacity.
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Driving with a Trailer
A CAUTION: I
0
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If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can’t see
or smell
CO. It can cause unconsciousness or
death. (See ‘(Engine Exhaust” in the Index.) To
maximize your safety when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle.
Do not use
RECIRCULATION because it only
recirculates the air inside your vehicle. (See
“Comfort Controls” in the Index.)
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
arc
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 1
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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Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re
a good deal
longer,
you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then,
to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and,
if
possible, have someone guide you.
Making Turns
NOTICE:
~~
Making very sharp turns while trailering could
cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal.
Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects.
Avoid jerky or
sudden maneuvers. Signal well
in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy-duty turn signal flasher.
The arrows on your instrument panel will flash
whenever you signal a
turn or lane change. Properly
hooked up,
the trailer lamps will also flash, telling other
drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows
on your instrument
panel will flash for turns even
if the bulbs on the trailer
are burned out. Thus, you may think drivers behind you
are seeing your signal when
they are not. It’s important
to check occasionally
to be sure the trailer bulbs are
still working.
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Driving On Grades
Reduce speed and shift to a 1owe.r gear Iwfow you start
down a long or steep downgrade.
If you don’t shift
down. you might have to use your brakes
so much that
they would get hot and no longer work well.
On
a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.
You should use DRIVE
(D) when towing a trailer.
Operating your vehicle
in DRIVE (D) when towing a
trailer
will minimize heat buildup and extend the life of
your transmission.
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a lower
temperature than at normal altitudes.
If you twn your
engine off imnlediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating.
To avoid this, let the engine run while
parked (preferably on level ground)
with the automatic
transmission
in PARK (PI for a few minutes before turning
the engine off.
If you do get the overheat warning. see
”Engine Overheating”
in the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached.
on a hill. If‘ something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here‘s
how
to do it:
1.
-. 3
3.
4.
5.
Apply your regular brakes, but don’t shift into
PARK
(P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes
until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking
brake, and then shift into PARK
(P).
Release the regular brakes.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s
a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
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Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing
Your Vehicle
Engine Overheating Engine
Fan Noise
If a Tire Goes Flat
Changing a Flat Tire
If You’re Stuck: In Sand, Mud,
Ice or Snow
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Towing Your Vehicle
Try to have a GM dealer or a proressional towing
service tow your vehicle. See "Roadside Assistance"
in
the Index.
If your vehicle has been changed since it was
factory-new by adding things like fog lamps, aero
skirting, or special tires and wheels, these instructions
may not be correct.
Before you do anything, turn
on the hazard
warning flashers.
When you call,
tell the towing service:
0 That your vehicle has four-wheel drive.
0 The make, model and year of your vehicle.
0 Whether you can rnolle the shift lever for the
transmission and shift the transfer case.
0 If there was an accident, what was damaged.
When the towing service arrives,
let the tow operator
know that this manual contains these towing
instructions. The operator may want to see them.
To help avoid injury to you or others:
0 Never let passengers ride in a vehicle that is
Never tow faster than safe or posted speeds.
Never tow with damaged parts not
Never get under your vehicle after it has
Always use separate safety chains on each
0 Never use J-hooks. Use T-hooks instead.
being
towed.
fully secured.
been lifted by the tow truck.
side when towing
a vehicle.
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JTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause
a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle. Always use
T-hooks inserted in the T-hook slots. Never use
J-hooks. They will damage drivetrain and
suspension components.
When your vehicle is being towed, have the ignition key
turned
to the OFF position. The steering wheel should
be clamped
in a straight-ahead position with a clamping
device designed for towing service.
Do not use the
vehicle’s steering column lock for this. The transmission
should be in NEUTRAL
(N) and the transfer case
should be
in 2HI. The parking brake should be released.
If your vehicle has no electrical power, the electrical
solenoid lock
must be overridden to shift from
PARK (P) to NEUTRAL (N). Follow these steps:
1 I Remove the wood trim panel surrounding the base
2. Reach inside the console and find the white of the shift lever.
solenoid lever.
(ii
3. Push the solenoid
lever down.
4. While holding the solenoid lever in the unlock
position, press the shift lever button and shift into
NEUTRAL
(N).
5. Release the solenoid lever and replace the trim panel.
Don’t have your vehicle towed on the drive wheels
unless
you must. If the vehicle must be towed on the
drive wheels, be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged. If these limitations must be exceeded, then
the drive wheels have to be supported
on a dolly.
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