2006 GMC SAVANA engine

You will need a well-charged battery (or batteries) to
restart the vehicle, and possibly for signaling later
on with your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window
almost all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you do not want to
spin your wheels too fast. The method known as rocking
can help you get out when you are stuck, but you
must use caution.
{CAUTION:
If you let your tires spin at high speed, they
can explode, and you or others could be
injured. And, the transmission or other parts of
the vehicle can overheat. That could cause an
engine compartment re or other damage.
When you are stuck, spin the wheels as little
as possible. Do not spin the wheels above
35 mph (55 km/h) as shown on the
speedometer.
Notice:Spinning your wheels can destroy parts of
your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
For more information about using tire chains on your
vehicle, seeTire Chains on page 5-68.
4-29

Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
•There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live
but also where you’ll be driving. A good source for
this information can be state or provincial police.
•Consider using a sway control. See “Hitches” later
in this section.
•Don’t tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
•Then, during the first 500 miles (800 km) that you
tow a trailer, don’t drive over 50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
•See also “Driving on Grades” later in this section.
Three important considerations have to do with weight:
•the weight of the trailer
•the weight of the trailer tongue
•and the weight on your vehicle’s tires
Tow/Haul Mode
Tow/haul is designed to assist while your vehicle is
pulling a large or heavy load or trailer. Tow/haul is most
useful while pulling such a load in rolling terrain, in
stop-and-go traffic, or when you need improved
low-speed control, such as when parking. The purpose
of the tow/haul mode is to:
•Reduce the frequency and improve the predictability
of transmission shifts,
•provide the same solid shift feel when pulling a
heavy load as when the vehicle is unloaded,
•improve control of vehicle speed while requiring
less throttle pedal activity.
4-38

Press this button located
to the right of the steering
wheel on the instrument
panel to turn tow/haul
mode on and off.
While activated, the
indicator light on the
instrument panel will
be on.
Tow/haul mode will turn off automatically when the
ignition is turned off. SeeTow/Haul Mode Light
on page 3-42.Tow/haul is most effective when the vehicle and trailer
combined weight is at least 75 percent of the vehicle’s
Gross Combined Weight Rating (GCWR). See “Weight
of the Trailer” later in this section.
Driving with tow/haul activated without a heavy load will
cause reduced fuel economy and unpleasant engine
and transmission driving characteristics, but will
not cause damage.
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. It can also depend on any
special equipment that you have on your vehicle,
and the amount of tongue weight the vehicle can carry.
See “Weight of the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated assuming only the
driver is 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.
4-39

If you’ll be pulling a trailer that, when loaded, will weigh
more than 5,000 lbs (2 270 kg), be sure to use a
properly mounted weight-distributing hitch and sway
control of the proper size. This equipment is very
important for proper vehicle loading and good handling
when you’re driving. You should always use a sway
control if your trailer will weigh more than these limits.
You can ask a hitch dealer about sway controls.
Will you have to make any holes in the body of your
vehicle when you install a trailer hitch?
If you’re using the wiring provided with the
factory-installed trailering package, you should not need
to make any holes in the body of your vehicle.
However, if you have an aftermarket hitch installed, you
may need to make holes in the body.
If you do, then be sure to seal the holes later when you
remove the hitch. If you don’t seal them, deadly
carbon monoxide (CO) from your exhaust can get into
your vehicle as well as dirt and water. See “Carbon
Monoxide” underEngine Exhaust on page 2-26.Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the
tongue of the trailer to help prevent the tongue from
contacting the road if it becomes separated from
the hitch. Instructions about safety chains may be
provided by the hitch manufacturer or by the trailer
manufacturer. Follow the manufacturer’s
recommendation for attaching safety chains and do not
attach them to the bumper. Always leave just enough
slack so you can turn with your rig. Never allow
safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes – and they must be
adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install,
adjust and maintain them properly.
Since your vehicle is equipped with StabiliTrak
®, your
trailer brake system cannot tap into the vehicle’s
hydraulic brake system.
4-47

Driving with a Trailer
{CAUTION:
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 not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-26. 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
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. See Climate Control System
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 are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts 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 would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
4-48

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 turn your
engine off immediately 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 (P) for a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-24.
Parking on Hills
{CAUTION:
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. 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.2. Have someone place chocks under the
trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and then shift to PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
•start your 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.
4-50

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 system. 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.
Trailer Wiring Harness
The optional heavy-duty trailer wiring package includes
a seven-wire harness assembly at the rear of the
vehicle and a four-wire harness assembly under the left
hand side of the instrument panel. The seven-wire
harness assembly is taped together and located in a
frame pocket at the driver side rear left corner of
the frame. The seven-wire harness includes a 30-amp
feed wire. Both harnesses come without connectors and
should be wired by a qualified electrical technician.
The technician can use the following color code chart
when connecting the wiring harness to your trailer
and trailer brake controller.Seven-Wire Harness
•Light Green: Back-up lamps
•Brown: Parking lamps
•Yellow: Left stoplamp and turn signal
•Dark Green: Right stoplamp and turn signal
•Dark Blue: Use for electric trailer brakes
•Orange: Trailer accessory
•White (heavy gage): Ground wire
Four-Wire Harness (Trailer Brake Controller)
•Black: Ground
•Red/White Stripe: Fused Battery
•Dark Blue: Trailer Brake Feed
•Light Blue: Fused Stoplamp/CHMSL
4-51

Service............................................................5-3
Accessories and Modifications..........................5-3
California Proposition 65 Warning.....................5-4
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 Specifications....................................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 (Gasoline Engine)..........................5-13
Engine Oil Life System (Gasoline Engine)........5-16
Engine Air Cleaner/Filter................................5-17
Automatic Transmission Fluid.........................5-19
Engine Coolant.............................................5-21
Radiator Pressure Cap..................................5-24
Engine Overheating.......................................5-24Cooling System............................................5-26
Engine Fan Noise.........................................5-32
Power Steering Fluid.....................................5-32
Windshield Washer Fluid................................5-34
Brakes........................................................5-35
Battery........................................................5-38
Jump Starting...............................................5-39
All-Wheel Drive..............................................5-43
Rear Axle.......................................................5-44
Front Axle......................................................5-44
Noise Control System.....................................5-45
Tampering with Noise Control System
Prohibited.................................................5-45
Bulb Replacement..........................................5-46
Halogen Bulbs..............................................5-46
Headlamps..................................................5-47
Front Turn Signal, Sidemarker and
Parking Lamps..........................................5-48
Center High-Mounted Stoplamp (CHMSL).........5-49
Taillamps.....................................................5-49
Replacement Bulbs.......................................5-50
Windshield Wiper Blade Replacement..............5-51
Section 5 Service and Appearance Care
5-1