2006 GMC ENVOY DENALI automatic transmission

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Oil Life System..................................5-20
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-35Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps....................................5-50
Taillamps, Turn Signal, and Stoplamps............5-51
Back-Up Lamps............................................5-52
Replacement Bulbs.......................................5-52
Windshield Wiper Blade Replacement..............5-53
Tires..............................................................5-55
Tire Sidewall Labeling...................................5-56
Tire Terminology and Denitions.....................5-59
Ination - Tire Pressure.................................5-62
Tire Inspection and Rotation...........................5-63
When It Is Time for New Tires.......................5-65
Buying New Tires.........................................5-66
Different Size Tires and Wheels......................5-67
Uniform Tire Quality Grading..........................5-68
Section 5 Service and Appearance Care
5-1

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
B. Engine Coolant Recovery Tank. SeeCooling System
on page 5-30.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-37.
D. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-36.
E. Automatic Transmission Fluid Dipstick (Out of View).
See “Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-23.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-16.G. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-28.
H. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-16.
I. Remote Negative (−) Terminal (Marked GND). See
Jump Starting on page 5-42.
J. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-38.
K. Battery. SeeBattery on page 5-41.
L. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 5-103.
5-13

A. Engine Coolant Recovery Tank. SeeCooling System
on page 5-30.
B. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-37.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-16.
E. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-23.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-16.G. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-28.
H. Remote Negative (−) Terminal (Marked GND). See
Jump Starting on page 5-42.
I. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-36.
J. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-38.
K. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 5-103.
L. Battery. SeeBattery on page 5-41.
5-15

Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission uid
level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-12.
How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), drive the vehicle
in THIRD (3) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold uid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for ve minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C), you
may have to idle the engine longer. Should the uid
level be low during this cold check, you must check the
uid hot before adding uid. Checking the uid hot
will give you a more accurate reading of the uid level.
5-23

Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift lever
in PARK (P).
3. With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position
the shift lever in PARK (P).
4. Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow these steps:
1. Flip the handle up and then pull out 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’s side of the
vehicle.
SeeEngine Compartment Overview on page 5-12
for more information on location.
2. Push it back in all the way, wait three seconds and
then pull it back out again.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, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
Consistency of Readings
Always check the uid level at least twice using the
procedure described previously. Consistency (repeatable
readings) is important to maintaining proper uid level. If
inconsistent readings persist, contact your dealer.
5-24

How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission uid to use. SeeRecommended
Fluids and Lubricants on page 6-12.
Add uid only after checking the transmission uid while
it is hot. A cold check is used only as a reference. If
the uid level is low, add only enough of the proper uid
to bring the level up to the HOT area for a hot check.
It does not take much uid, generally less than one pint
(0.5 L). Do not overll.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-28.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-25

Jump Starting
If your vehicle’s battery has run down, you may want to
use another vehicle and some jumper cables to start
your vehicle. Be sure to use the following steps to do
it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode
or ignite.
They contain enough electricity to
burn you.
If you do not follow these steps exactly, some
or all of these things can hurt you.Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. You would not be able
to start your vehicle, and the bad grounding
could damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake rmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake. If
you have a four-wheel-drive vehicle, be sure
the transfer case is not in NEUTRAL.
5-42

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to
its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-62.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation (DOT) motor vehicle
safety standards. The DOT code includes the Tire
Identication Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand, and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-45.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-45.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-45.
5-59