2001 GMC ENVOY clutch

2-52
Increasing Speed While Using Cruise Control
There are two ways to go to a higher speed:

Use the accelerator pedal to get to the higher speed.
Press the button at the end of the lever, then release
the button and the accelerator pedal. You'll now
cruise at the higher speed.

Move the cruise switch from ON to R/A. Hold it
there until you get up to the speed you want, and
then release the switch. To increase your speed in
very small amounts, move the switch briefly to R/A.
Each time you do this, your vehicle will go about
1 mph (1.6 km/h) faster.
Reducing Speed While Using Cruise Control

Press in the SET button at the end of the lever until
you reach the lower speed you want, then release it.

To slow down in very small amounts, press the SET
button briefly. Each time you do this, you'll go about
1 mph (1.6 km/h) slower.
Passing Another Vehicle While Using Cruise Control
Use the accelerator pedal to increase your speed. When
you take your foot off the pedal, your vehicle will slow
down to the cruise control speed you set earlier.Using Cruise Control on Hills
How well your cruise control will work on hills depends
upon your speed, load and the steepness of the hills.
When going up steep hills, you may want to step on the
accelerator pedal to maintain your speed. When going
downhill, you may have to brake or shift to a lower gear
to keep your speed down. Of course, applying the brake
takes you out of cruise control. Many drivers find this to
be too much trouble and don't use cruise control on
steep hills.
Ending Cruise Control
There are two ways to turn off the cruise control:

Step lightly on the brake pedal or push the clutch
pedal, if you have a manual transmission.

Move the cruise switch to OFF.
Erasing Speed Memory
When you turn off the cruise control or the ignition,
your cruise control set speed memory is erased.
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4-22

As you are backing down the hill, put your left hand
on the steering wheel at the 12 o'clock position.
This way, you'll be able to tell if your wheels are
straight and maneuver as you back down. It's best
that you back down the hill with your wheels straight
rather than in the left or right direction. Turning the
wheel too far to the left or right will increase the
possibility of a rollover.
Here are some things you must not do if you stall, or are
about to stall, when going up a hill.

Never attempt to prevent a stall by shifting into
NEUTRAL (N) (or depressing the clutch, if you
have a manual transmission) to ªrev
-upº the
engine and regain forward momentum. This won't
work. Your vehicle will roll backwards very quickly
and you could go out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift to
REVERSE (R), release the parking brake, and
slowly back straight down.
Never attempt to turn around if you are about to
stall when going up a hill. If the hill is steep enough
to stall your vehicle, it's steep enough to cause you
to roll over if you turn around. If you can't make it
up the hill, you must back straight down the hill.
Q:Suppose, after stalling, I try to back down
the hill and decide I just can't do it.
What should I do?
A:Set the parking brake, put your transmission
in PARK (P) (or the manual transmission in
FIRST (1)) and turn off the engine. Leave the
vehicle and go get some help. Exit on the uphill
side and stay clear of the path the vehicle would
take if it rolled downhill. Do not shift the transfer
case to NEUTRAL when you leave the vehicle.
Leave it in some gear.
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4-24
CAUTION:
Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could cause
loss of control and a serious accident. Apply the
brakes lightly when descending a hill and use a
low gear to keep vehicle speed under control.
Q:Are there some things I should not do
when driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a
serious accident.

When driving downhill, avoid turns that take you
across the incline of the hill. A hill that's not too
steep to drive down may be too steep to drive across.
You could roll over if you don't drive straight down.
Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal
pressed down in a manual shift. This is called
ªfree
-wheeling.º Your brakes will have to do
all the work and could overheat and fade.
Q:Am I likely to stall when going downhill?
A:It's much more likely to happen going uphill.
But if it happens going downhill, here's what to do.

Stop your vehicle by applying the regular brakes.
Apply the parking brake.

Shift to PARK (P) (or to NEUTRAL (N) with the
manual transmission) and, while still braking, restart
the engine.

Shift back to a low gear, release the parking brake,
and drive straight down.

If the engine won't start, get out and get help.
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5-17
Engine Fan Noise
This 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 you start the
engine. It will go away as the fan clutch disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a
few tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off
the accelerator pedal and grip the steering wheel firmly.
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'd 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.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
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6-
6-1
Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-6 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-11 Engine Oil
6
-16 Engine Air Cleaner/Filter
6
-17 Automatic Transmission Fluid
6
-20 Manual Transmission Fluid
6
-21 Hydraulic Clutch
6
-22 Rear Axle
6
-22 Four-Wheel Drive
6
-24 Engine Coolant
6
-27 Radiator Pressure Cap
6
-28 Power Steering Fluid
6
-28 Windshield Washer Fluid6
-30 Brakes
6
-34 Battery
6
-35 Bulb Replacement
6
-42 Windshield Wiper Blade Replacement
6
-44 Tires
6
-53 Appearance Care
6
-53 Cleaning the Inside of Your Vehicle
6
-56 Care of Safety Belts
6
-57 Cleaning the Outside of Your Vehicle
6
-61 GM Vehicle Care/Appearance Materials
6
-62 Vehicle Identification Number (VIN)
6
-62 Service Parts Identification Label
6
-63 Electrical System
6
-72 Replacement Bulbs
6
-72 Capacities and Specifications
6
-73 Normal Maintenance Replacement Parts
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6-21 How to Add Fluid
Here's how to add fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use. See
ªRecommended Fluids and Lubricantsº in the Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the fluid level up to the bottom of the
filler plug hole.
3. Install the filler plug. Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self
-adjusting. The clutch master cylinder reservoir is
filled with hydraulic clutch fluid.
It is not necessary to regularly check clutch fluid unless
you suspect there is a leak in the system. Adding fluid
won't correct a leak.
A fluid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance Schedule to determine how
often you should check the fluid level in your clutch
master cylinder reservoir and for the proper fluid. See
ªOwner Checks and Servicesº and ªRecommended
Fluids and Lubricantsº in the Index.
How to Check and Add Fluid
The proper fluid should be added if the level does not
reach the bottom of the diaphragm when it's in place in
the reservoir. See the instructions on the reservoir cap.
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6-68
Name Usage
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging IGN 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
IGN C Starter Solenoid,
Fuel Pump, PRNDL
HTDSEAT Heated Seat
HVAC HVAC SystemName Usage
TRCHMSL Trailer Center High Mount
Stop Light
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
HAZLP Hazard Lamps
VECHMSL Vehicle Center High
-Mounted
Stop Lamp
HTDMIR Heated Mirror
ATC Transfer Case (Four
-Wheel Drive)
STOPLP Stop Lamps
RR W/W Rear Window Wiper
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6-71
Name Usage
RAP Retained Accessory Power
LDLEV Electronic Load Leveling
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging, IGN 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
IGN C Starter Solenoid, Fuel Pump,
PRNDL
HTDSEAT Heated Seats
HVAC HVAC SystemName Usage
TRCHMSL Trailer Center High
-Mounted
Stop Lamp
HI BEAM High
-Beam Headlamps
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
HAZLP Hazard Lamps
VECHMSL Vehicle Center
High
-Mounted Stoplamp
HTDMIR Heated Mirror
ATC Automatic Transfer Case
STOPLP Stoplamps
RR W/W Rear Window Wiper
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