Fuel E85 (85% Ethanol)
If the vehicle has the 4.8L V8 engine (VIN Code A), the
5.3L V8 engine (VIN Code 4), or the 6.0L V8 engine
(VIN Code G) and the N15 flexible fuel option, you can
use either unleaded gasoline or ethanol fuel containing
up to 85% ethanol (E85). SeeFuel on page 6-5.In
all other engines, use only the unleaded gasoline
described underGasoline Octane on page 6-6.
Vehicles that have the 4.8L V8 engine (VIN Code A),
the 5.3L V8 engine (VIN Code 4), or the 6.0L V8 engine
(VIN Code G) and the N15 flexible fuel option have a
yellow fuel cap and can use 85% ethanol fuel (E85). See
Fuel E85 (85% Ethanol) on page 6-8.
Driving for Better Fuel Economy
Driving habits can affect fuel mileage. Here are some
driving tips to get the best fuel economy possible.
•Avoid fast starts and accelerate smoothly.
•Brake gradually and avoid abrupt stops.
•Avoid idling the engine for long periods of time.
•When road and weather conditions are appropriate,
use cruise control, if equipped.
•Always follow posted speed limits or drive more
slowly when conditions require.
•Keep vehicle tires properly inflated.
•Combine several trips into a single trip.
•Replace the vehicle’s tires with the same TPC Spec
number molded into the tire’s sidewall near the size.
•Follow recommended scheduled maintenance.
Roadside Assistance Program
U.S.:1-800-GMC-8782 (462-8782)
TTY Users:1-888-889-2438
Canada:1-800-268-6800
As the owner of a new GMC, you are automatically
enrolled in the Roadside Assistance program. This
program provides technically trained advisors who are
available 24 hours a day, 365 days a year, minor repair
information or towing arrangements.
Online Owner Center
The Online Owner Center is a complimentary service
that includes online service reminders, vehicle
maintenance tips, online owner manual, special
privileges and more.
Sign up today at:www.gmownercenter.com/gmc
(U.S.) orwww.gm.ca(Canada).
1-18
Restraint System Check
Checking the Restraint Systems
Safety Belts
Now and then, check that the safety belt reminder light,
safety belts, buckles, latch plates, retractors, and
anchorages are all working properly.
Look for any other loose or damaged safety belt system
parts that might keep a safety belt system from doing
its job. See your dealer/retailer to have it repaired. Torn
or frayed safety belts may not protect you in a crash.
They can rip apart under impact forces. If a belt is torn
or frayed, get a new one right away.
Make sure the safety belt reminder light is working. See
Safety Belt Reminders on page 4-23for more
information.
Keep safety belts clean and dry. SeeCare of Safety
Belts on page 6-99.
Airbags
The airbag system does not need regularly scheduled
maintenance or replacement. Make sure the airbag
readiness light is working. SeeAirbag Readiness Light
on page 4-23for more information.
Notice:If an airbag covering is damaged, opened,
or broken, the airbag may not work properly. Do
not open or break the airbag coverings. If there are
any opened or broken airbag covers, have the
airbag covering and/or airbag module replaced. For
the location of the airbag modules, seeWhat
Makes an Airbag Inflate? on page 2-66. See your
dealer/retailer for service.
2-79
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in
kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem causing
low oil pressure. Check your oil as soon as possible.
{WARNING:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil. United States
Canada
4-34
Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.This light comes on briefly while starting the engine. If it
does not, have the vehicle serviced by your dealer/
retailer. If the system is working normally the indicator
light then goes off.
If the light comes on and stays on, it means that oil is
not flowing through the engine properly. The vehicle
could be low on oil and it might have some other system
problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
PASS-Key
®III+ Electronic
Immobilizer Operation
on page 3-20.
4-35
Vehicle Information Menu Items
T
(Vehicle Information):Press this button to scroll
through the following menu items:
Oil Life
Press the vehicle information button until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 4-44. You should
change the oil as soon as possible. SeeEngine Oil on
page 6-15. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 7-3for
more information.
Remember, you must reset the OIL LIFE yourself after
each oil change. It will not reset itself. Also, be
careful not to reset the OIL LIFE accidentally at any
time other than when the oil has just been changed.It cannot be reset accurately until the next oil change.
To reset the engine oil life system, seeEngine Oil
Life System on page 6-18.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units.
Tire Pressure
If your vehicle has the Tire Pressure Monitor System
(TPMS), the pressure for each tire can be viewed in
the DIC. The tire pressure will be shown in either
kilopascals (kPa) or pounds per square inch (psi). Press
the vehicle information button until the DIC displays
FRONT TIRES PSI (kPa) LEFT ## RIGHT ##. Press the
vehicle information button again until the DIC displays
REAR TIRES PSI (kPa) LEFT ## RIGHT ##.
If a low tire pressure condition is detected by the system
while driving, a message advising you to check the
pressure in a specific tire will appear in the display. See
In ation - Tire Pressure on page 6-63andDIC Warnings
and Messages on page 4-44for more information.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
4-41
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
fluid, 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 optional heavy-duty trailer wiring package includes
a wiring harness, with a seven-pin connector at the
rear of the vehicle and a four-wire harness assembly
under the driver side of the instrument panel. The
four-wire harness assembly comes without a connector.
If the vehicle does not have a trailer hitch, the
seven-wire harness assembly with connector is taped
together and located in a frame pocket at the driver side
rear left corner of the frame.
If the vehicle has a trailer hitch, the seven-wire harness
assembly with connector is attached to a bracket on
the hitch platform. In both cases, the seven-wire harness
has a connector and includes a 30-amp feed wire.
5-37
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Scheduled Maintenance on page 7-3, and be sure to
use the transmission fluid listed inRecommended Fluids
and Lubricants on page 7-11.
How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer 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
parts 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 fluid level if you have been driving:
•When outside temperatures are above 32°C (90°F).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
To get the right reading, the fluid should be at
normal operating temperature, which is 82°C to 93°C
(180°F to 200°F).
Get the vehicle warmed up by driving about 24 km
(15 miles) when outside temperatures are above
10°C (50°F). If it is colder than 10°C (50°F), drive the
vehicle in D (DRIVE) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold fluid 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 five minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 10°C (50°F), you
may have to idle the engine longer. Should the fluid
level be low during this cold check, you must check the
fluid hot before adding fluid. Checking the fluid hot
will give you a more accurate reading of the fluid level.
6-21
How to Add Automatic Transmission
Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 7-11.
Using a funnel, add fluid down the transmission dipstick
tube only after checking the transmission fluid while it
is hot. A cold check is used only as a reference. If
the fluid level is low, add only enough of the proper fluid
to bring the level up to the HOT area for a hot check.
It does not take much fluid, generally less than one pint
(0.5 L). Do not overfill.
Notice:Use of the incorrect automatic transmission
uid may damage the vehicle, and the damages
may not be covered by the vehicle’s warranty.
Always use the automatic transmission uid listed
inRecommended Fluids and Lubricants on
page 7-11.
•After adding fluid, recheck the fluid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
•When the correct fluid level is obtained, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.
Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
fluid level. The only reason for fluid loss is a
transmission leak or overheating the transmission. If a
small leak is suspected, use the following procedures to
check the fluid level. However, if there is a large leak,
then it may be necessary to have the vehicle towed to a
dealer/retailer service department and have it repaired
before driving the vehicle further.
Change the fluid and filter at the intervals listed in
Scheduled Maintenance on page 7-3, and be sure to
use the transmission fluid listed inRecommended Fluids
and Lubricants on page 7-11.
How to Check Automatic Transmission
Fluid
Because this operation can be difficult, it is
recommended to have this check done at the
dealer/retailer service department, which can monitor
the transmission temperature. The transmission
fluid level increases with temperature. To obtain a highly
accurate fluid level check, the transmission temperature
must be measured.
6-23