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Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. See ªParking Brakeº in the Index if necessary.
NOTE: Do not use the accelerator pedal, and be
ready to turn off the engine immediately if it starts.
3. On automatic transmission vehicles, try to start the
engine in each gear. The starter should work only in
PARK (P) or NEUTRAL (N). If the starter works
in any other position, your vehicle needs service.
On manual transmission vehicles, put the shift lever
in NEUTRAL (N), push the clutch down halfway
and try to start the engine. The starter should work
only when the clutch is pushed down all the way to
the floor. If the starter works when the clutch isn't
pushed all the way down, your vehicle needs service.Automatic Transmission Shift Lock Control
System Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room around
the vehicle. It should be parked on a level surface.
2. Firmly apply the parking brake. See ªParking Brakeº
in the Index if necessary.
NOTE: Be ready to apply the regular brake
immediately if the vehicle begins to move.
3. With the engine off, turn the key to the RUN position,
but don't start the engine. Without applying the
regular brake, try to move the shift lever out of
PARK (P) with normal effort. If the shift lever
moves out of PARK (P), your vehicle needs service.
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7-46
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
With an automatic transmission, the key should turn
to LOCK only when the shift lever is in PARK (P).
With a manual transmission, the key should turn to
LOCK only when you press the key release button.
On all vehicles, the key should come out only in LOCK.
Parking Brake and Automatic Transmission
PARK (P) Mechanism Check
CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in case
it begins to roll. Be ready to apply the regular
brake at once should the vehicle begin to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake,
set the parking brake.
To check the parking brake's holding ability:
With the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure
from the regular brake pedal. Do this until the
vehicle is held by the parking brake only.
To check the PARK (P) mechanism's holding
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
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Page 431 of 448
7-50
USAGEFLUID/LUBRICANT
Manual
TransmissionSynchromesh Transmission Fluid
(GM Part No. 12345349
or equivalent).
Automatic
TransmissionDEXRON-III Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant,
Superlube (GM Part
No. 12346241 or equivalent).
Chassis
LubricationChassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
Front and Rear
Axle (Standard
Differential)SAE 80W-90 Axle Lubricant
(GM Part No. 1052271
or equivalent).
USAGEFLUID/LUBRICANT
Rear Axle
(Locking
Differential)Axle Lubricant; use only GM
Part No. 1052271. Do not add
friction modifier.
Automatic
Transfer CaseAUTO-TRAK II Fluid
(GM Part No. 12378508).
Rear Driveline
Center Spline and
Universal JointsChassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
Constant
Velocity
Universal JointChassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
ProCarManuals.com
Page 447 of 448
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)
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Page 448 of 448
8-13
PUBLICATION FORM
NUMBEROrders will be mailed within 10 days of receipt. Please allow adequate time for postal
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
information within 30 days of delivery. On returns, a re-stocking fee may be applied
against the original order. ORDER TOLL FREE
(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
Canadian Postage
GRAND TOTAL
add 6% sales tax
GM-GMC-ORD99 *(Prices are subject to change without notice and without incurring
obligation. Allow ample time for delivery.)Note to Canadian Customers: All listed prices are quoted in U.S. funds. Canadian residents
are to make checks payable in U.S. funds.
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only Ð
do not send cash.)
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Transmission Unit Repair
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