2-26
NEUTRAL (N): In this position, your engine doesn't
connect with the wheels. To restart when you're already
moving, use NEUTRAL (N) only. Also, use
NEUTRAL (N) when your vehicle is being towed.
CAUTION:
Shifting out of PARK (P) or NEUTRAL (N) while
your engine is ªracingº (running at high speed) is
dangerous. Unless your foot is firmly on the
brake pedal, your vehicle could move very
rapidly. You could lose control and hit people or
objects. Don't shift out of PARK (P) or
NEUTRAL (N) while your engine is racing.
NOTICE:
Damage to your transmission caused by shifting
out of PARK (P) or NEUTRAL (N) with the
engine racing isn't covered by your warranty.
DRIVE (D): This position is for normal driving.
If you need more power for passing, and you're:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You'll shift down to the next gear and have more power.
THIRD (3): This position is also used for normal
driving, however, it offers more power and lower fuel
economy than DRIVE (D). You should use THIRD (3)
when carrying a heavy load or driving on steep hills.
You should use THIRD (3) (or, as you need to, a lower
gear) when towing a trailer to minimize heat build
-up
and extend the life of your transmission.
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND (2) on hills.
It can help control your speed as you go down steep
mountain roads, but then you would also want to use
your brakes off and on. If you manually select
SECOND (2), the transmission will drive in
SECOND (2). You may use this feature for reducing
torque to the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
4-42 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 is a
seven
-wire harness assembly. The four-wire portion of
the harness assembly is stored under the vehicle, along
the driver's side rear corner of the frame rail. The
three
-wire portion of the harness assembly is stored in a
frame pocket under the rear of the vehicle, on the
driver's side. The heavy
-duty trailer wiring harness has
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.Four
-Wire Harness
Light Green: Back
-up lamps
Brown: Parking lamps
Yellow: Left stoplamp and turn signal
Dark Green: Right stoplamp and turn signal
Three
-Wire Harness
Dark Blue: Use for electric trailer brakes
(seven
-wire harness only)
Orange: Trailer accessory (seven
-wire harness only)
White (heavy gage): Ground wire
Securely attach the harness to the trailer, then tape or
strap it to your vehicle's frame rail. Be sure you leave it
loose enough so the wiring doesn't bend or break, but
not so loose that it drags on the ground. Store the
harness in its original place. Wrap the harness together
and tie it neatly so it won't be damaged.
5-4
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
NOTICE:
If the other system isn't a 12-volt system with a
negative ground, both vehicles can be damaged.
If you have a diesel engine vehicle with two batteries
(or more) you should know before you begin that,
especially in cold weather, you may not be able to
get enough power from a single battery in another
vehicle to start your diesel engine.
If your vehicle has more than one battery, use the
battery that is under the hood of the vehicle. This
will reduce the electrical resistance.2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't 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 firmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) and a manual transmission
in NEUTRAL.
3. Turn off the ignition on both vehicles. Turn off all
lamps that aren't needed, and radios. This will avoid
sparks and help save both batteries, and could save
your radio.
8-12
2001 GMC SERVICE PUBLICATIONS ORDERING INFORMATION
The following publications covering the operation and servicing of your vehicle can be purchased by filling out
the Service Publication Order Form in this book and mailing it in with your check, money order,
or credit card information to Helm, Incorporated (address below.)
CURRENT PUBLICATIONS FOR 2001 GMC
SERVICE MANUALS
Service Manuals have the diagnosis and repair information
on engines, transmission, axle, suspension, brakes,
electrical, steering, body, etc.
RETAIL SELL PRICE: $120.00
TRANSMISSION, TRANSAXLE, TRANSFER CASE
UNIT REPAIR MANUAL
This manual provides information on unit repair service
procedures, adjustments and specifications for the
2001 GM transmissions, transaxles and transfer cases.
RETAIL SELL PRICE: $50.00
SERVICE BULLETINS
Service Bulletins give technical service information needed
to knowledgeably service General Motors cars and trucks.
Each bulletin contains instructions to assist in the
diagnosis and service of your vehicle.OWNER'S INFORMATION
Owner publications are written directly for Owners and
intended to provide basic operational information about the
vehicle. The owner's manual will include the Maintenance
Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner's Manual and
Warranty Booklet.
RETAIL SELL PRICE: $20.00
Without Portfolio: Owner's Manual only.
RETAIL SELL PRICE: $15.00
CURRENT & PAST MODEL ORDER FORMS
Service Publications are available for current and past
model GM vehicles. To request an order form, please
specify year and model name of the vehicle.
PLEASE COMPLETE THE ORDER FORM SHOWN ON
THE FOLLOWING PAGE AND MAIL TO:
Helm, Incorporated P.O. Box 07130 Detroit, MI 48207OR ORDER TOLL FREE: 1-800-551-4123
Monday-Friday 8:00 AM ± 6:00 PM Eastern Time
Visit Helm, Inc. on the World Wide Web at: www.helminc.com
For Credit Card Orders Only (VISA±MasterCard±Discover)
8-13
PUBLICATION FORM
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service. If further information is needed, write to the address shown below or call
1-800-551-4123. Material cannot be returned for credit without packing slip with return
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(NOTE: For Credit Card Holders Only)1-800-551-4123(Monday-Friday 8:00 AM ± 6:00 PM EST)
FAX Orders Only 1-313-865-5927
Service Manual
NOTE: Dealers and Companies please provide dealer or company name, and also the
name of the person to whose attention the shipment should be sent.
Mail completed order form to:
HELM, INCORPORATED P.O. Box 07130 Detroit, MI 48207
For purchases outside U.S.A. please write to the above address for quotation.
2001$120.00
2001
$50.00
2001
$20.00
2001
$15.00
TOTAL MATERIAL
Michigan Purchasers
U.S. Order Processing$6.00
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GRAND TOTAL
add 6% sales tax
(See Note Below)
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are to make checks payable in U.S. funds. To cover Canadian postage, add $11.50 plus the
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