2002 GMC YUKON XL DENALI transmission

7-19
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.
Do not use the accelerator pedal, and be ready to turn
off the engine immediately if it starts.
3. 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.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.
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.

7-20
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.

The key should turn to LOCK only when the shift
lever is in PARK (P).

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.

7-23
Part D: Recommended Fluids
and Lubricants
Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
FLUID/LUBRICANT
Engine OilEngine oil with the American
Petroleum Institute Certified
for Gasoline Engines starburst
symbol of the proper viscosity.
To determine the preferred
viscosity for your vehicle's engine,
see ªEngine Oilº in the Index.
Engine Coolant50/50 mixture of clean,
drinkable water and use only
GM Goodwrench

DEX-COOL

or Havoline
DEX-COOL

Coolant. See ªEngine Coolantº
in the Index.
USAGEFLUID/LUBRICANT
Hydraulic
Brake SystemDelco Supreme 11
Brake Fluid
(GM Part No. 12377967 or
equivalent DOT
-3 brake fluid).
Windshield
Washer SolventGM Optikleen
Washer Solvent
(GM Part No. 1051515)
or equivalent.
Power
Steering SystemGM Power Steering Fluid
(GM Part No. 1052884
- 1 pint,
1050017
- 1 quart, 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.

7-24
USAGEFLUID/LUBRICANT
Front and
Rear AxleSAE 75W-90 Synthetic Axle
Lubricant (GM Part No. 12378261)
or equivalent meeting GM
Specification 9986115.
Transfer CaseDEXRON
-III Automatic
Transmission Fluid.
Front Axle
Propshaft SplineSpline Lubricant, Special Lubricant
(GM Part No. 12345879) or
lubricant meeting requirements
of GM 9985830.
Hood Latch
Assembly,
Secondary Latch,
Pivots, Spring
Anchor and
Release PawlLubriplate
Lubricant Aerosol
(GM Part No. 12346293 or
equivalent) or lubricant meeting
requirements of NLGI # 2,
Category LB or GC
-LB.
USAGEFLUID/LUBRICANT
Hood HingesMulti-Purpose Lubricant,
Superlube
(GM Part
No. 12346241 or equivalent).
Body Door
Hinge Pins,
Tailgate Hinge
and Linkage,
Folding Seat and
Fuel Door HingeMulti-Purpose Lubricant,
Superlube
(GM Part
No. 12346241 or equivalent).
Outer
Tailgate Handle
Pivot PointsMulti-Purpose Lubricant,
Superlube
(GM Part
No. 12346241 or equivalent).
Weatherstrip
ConditioningDielectric Silicone Grease (GM
Part No. 12345579 or equivalent).
Weatherstrip
SqueaksSynthetic Grease with Teflon,
Superlube
(GM Part
No. 12371287 or equivalent).

8-12
SERVICE PUBLICATIONS ORDERING INFORMATION
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 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 specifically 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: $35.00
Without Portfolio: Owner's Manual only.
RETAIL SELL PRICE: $25.00
Current and 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.
ORDER TOLL FREE: 1-800-551-4123 ± Monday-Friday 8:00 AM ± 6:00 PM Eastern TimeVisit Helm, Inc. on the World Wide Web at: www.helminc.com For Credit Card Orders Only (VISA-MasterCard-Discover)
Helm, Incorporated
P.O. Box 07130
Detroit, MI 48207
Prices are subject to change without notice and without Note to Canadian Customers: All listed prices are quoted in U.S. funds.
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