2009 GMC ENVOY tow

Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
start the engine,
shift into a gear, and
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
The vehicle needs service more often when pulling a
trailer. See this manual’s Maintenance Schedule
or Index for more information. Things that are especially
important in trailer operation are automatic transmission
uid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect
these before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle may have a seven-wire trailer towing
harness. This harness may have a seven-pin universal
heavy-duty trailer connector (if equipped with the
trailering package) that is attached to a bracket on
the hitch platform or included with the four-pin trailer
towing harness. If the vehicle is not equipped with the
heavy-duty trailer connector, one may be purchased from
your dealer/retailer.
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The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Electric BrakesIf towing a light-duty trailer with a standard four-way
round pin connector, an adapter connector is available
from your dealer/retailer.
If charging a remote (non-vehicle) battery, turn on the
headlamps to boost the vehicle system voltage and
properly charge the battery.
The vehicle is also equipped with wiring for an
electric trailer brake controller. These wires are
located inside the vehicle on the driver side under the
instrument panel. These wires should be connected
to an electric trailer brake controller by your
dealer/retailer or a qualied service center.
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A. Engine Coolant Recovery Tank. SeeCooling
System on page 5-24.
B. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-34.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
E. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-21.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Radiator Pressure Cap. SeeCooling System on
page 5-24.
H. Remote Negative (−) Terminal (Marked GND).
SeeJump Starting on page 5-39.
I. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-33.
J. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-35.
K. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 5-113.
L. Battery. SeeBattery on page 5-38.Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Then, without shutting off the engine, follow these steps:
1. Flip the handle up and then remove the dipstick
and wipe it with a clean rag or paper towel.
The automatic
transmission dipstick
handle with this symbol on
it is located in the engine
compartment on the
passenger side of the
vehicle.
SeeEngine Compartment Overview on page 5-12
for more information on location.
2. Reinstall it back in all the way, wait three seconds
and then pull it back out again. If the dipstick does
not go down the tube easily, turn the blade and
try again until it is fully inserted in the tube.3. Check both sides of the dipstick and read the lower
level. The uid level must be in the COLD area,
below the cross-hatched area, for a cold check or
in the HOT or cross-hatched area for a hot check.
Be sure to keep the dipstick pointed down to get an
accurate reading.
4. If the uid level is in the acceptable range, reinstall
the dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
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If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If the overheat warning is displayed with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drivethe vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for three
minutes while parked. If the warning is still displayed,
turn off the engine until it cools down.Engine Fan Noise
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 clutch is not engaged. This improves fuel economy
and reduces fan noise. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, the fan
speed increases when the clutch engages so you may
hear an increase in fan noise. 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 disengages.
You may also hear this fan noise when the engine is
started. The sound will go away as the fan clutch
disengages.
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Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-49.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and follow
the instructions on the bulb package.
Headlamps
To replace one of these bulbs:
1. Open the hood.Hood Release on page 5-11.
2. Lift the two headlamp retaining clips.3. Pull the headlamp assembly away from the vehicle
to access the electrical connectors.
4. Remove the cover from the headlamp bulb.
5. Turn the bulb socket counterclockwise and remove it.
6. Disconnect the electrical connector from the old bulb.
7. Plug the electrical connector into the new bulb using
care not to touch the glass with your ngers.
8. Turn the socket clockwise to reinstall it.
9. Reinstall the headlamp cover.
10. Push the headlamp assembly toward the vehicle.
11. Press down on the headlamp retaining clips to
secure the headlamp assembly.
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{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be sure
to use a scraper or wire brush later, if
needed, to get all the rust or dirt off. See
Changing a Flat Tire on page 5-88.
Make sure the spare tire, if the vehicle has one, is
stored securely. Push, pull, and then try to rotate or
turn the tire. If it moves, tighten the cable. See
Storing a Flat or Spare Tire and Tools on
page 5-100.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
inuence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining. Some
commercial truck tires
may not have treadwear
indicators.
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Tire Chains
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle without the
proper amount of clearance can cause damage to
the brakes, suspension, or other vehicle parts. The
area damaged by the tire chains could cause you to
lose control of the vehicle and you or others may be
injured in a crash. Use another type of traction
device only if its manufacturer recommends it for
use on the vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to the vehicle,
drive slowly, re-adjust or remove the device if it is
contacting the vehicle, and do not spin the wheels.
If you do nd traction devices that will t, install
them on the rear tires.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the at tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much
like a skid and may require the same correction you
would use in a skid. In any rear blowout remove
your foot from the accelerator pedal. Get the vehicle
under control by steering the way you want the vehicle
to go. It may be very bumpy and noisy, but you can
still steer. Gently brake to a stop, well off the road
if possible.
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