2001 GMC YUKON XL DENALI wheel

4-53
The seven-wire harness contains the following
trailer circuits:

Yellow: Left Stop/Turn Signal

Dark Green: Right Stop/Turn Signal

Brown: Taillamps

White: Ground

Light Green: Back
-up Lamps

Red: Battery Feed

Dark Blue: Trailer Brake
A jumper harness for an electric trailer brake controller
and a trailer battery feed fuse are included with this
trailering package. (See ªInstrument Panel Jumper
Wiring Harnessº later in this section.)
If you need to tow a light
-duty trailer with a standard
four
-way round pin connector, an adapter connector is
available from your dealer.Instrument Panel Jumper Wiring Harness
This harness is included with the heavy-duty and
camper/fifth
-wheel trailer wiring packages. The harness
is for an electric trailer brake controller and includes a
trailer battery feed fuse. This harness and fuse should be
installed by your dealer or a qualified service center.

5-17
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases as the clutch more fully engages. So you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional
cooling is not required and the clutch disengages.
You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
partially disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like
a skid and may require the same correction you'd use
in a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.

5-18
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning flashers.
CAUTION:
Changing a tire can cause an injury. The vehicle
can slip off the jack and roll over you or other
people. You and they could be badly injured.
Find a level place to change your tire. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine.
4. Put the wheel blocks at the front and
rear of the tire farthest away from the
one being changed. That would be the
tire on the other side of the vehicle, at
the opposite end.The following steps will tell you how to use the jack and
change a tire.

5-20
Denali XL Models
A. Bottle Jack
B. Wheel Blocks
C. Wing Nut
D. Mounting Bracket
E. Removable TrayF. Retaining Hook
G. Retaining Bracket
and Wing Nut
H. Tool Kit with Jack
Tools and GlovesDenali: The equipment you'll need is located under the
second row passenger's seat on the driver's side of the
vehicle, and behind the left trim panel on the driver's
side of the vehicle. Skip the first step and follow the
last three.
Denali XL: The equipment you'll need is located
under the storage tray in the rear trim panel on the
driver's side of the vehicle.
1. Remove the tray to access the tools.
2. There is a wing nut used to retain the tool kit.
To remove it, turn the wing nut counterclockwise.
3. To release the bottle jack from its holder, turn
the knob on the bottle jack counterclockwise
to lower the jack head.
4. The wheel blocks and the wheel block
retainer can be removed by turning the
wing nut counterclockwise.
You'll use the jack handle extensions and the wheel
wrench to remove the underbody
-mounted spare tire.

5-21
A. Hoist Assembly
B. Wheel Wrench
C. Jack
Handle Extensions
D. Hoist Shaft
E. Valve Stem,
Pointed Up
F. Spare TireG. Tire Retainer
H. Hoist Cable
I. Hoist Lock
J. Hoist Shaft
Access Hole
K. Hoist End of
Extension ToolFollow these instructions to lower the spare tire:
1. If the vehicle is equipped with a hoist lock (I), open
the spare tire lock cover on the bumper and use the
ignition key to remove the lock.
2. Assemble the wheel wrench (B) and the two jack
handle extensions (C) as shown. Insert the hoist
end (K) (open end) of the extension through the
hole (J) in the rear bumper. Be sure the hoist end
of the extension connects into the hoist shaft (D)
(the ribbed square end of the extension is used to
lower the spare tire).
3. Turn the wheel wrench counterclockwise to lower
the spare tire (F) to the ground. Continue to turn the
wheel wrench until the spare tire can be pulled out
from under the vehicle. The wheel wrench has a
hook that allows you to pull the hoist cable (H)
towards you, to assist in reaching the spare tire.
4. When the tire has been lowered, tilt the retainer at
the end of the cable so it can be pulled up through
the wheel opening.
5. Put the spare tire near the flat tire.

5-22
The tools you'll be using include the bottle jack (A), the
wheel blocks (B), the jack handle (C), the jack handle
extensions (D), and the wheel wrench (E).
If the flat tire is on a rear tire of the vehicle, you'll need
to use both jack handle extensions.Attach the wheel wrench to the jack handle extensions
(as needed). Attach the jack handle to the jack.

5-23
Turn the wheel wrench clockwise to raise the jack lift
head to the lifting point.
To remove the center cap
place the chisel end of the
wheel wrench in the slot
on the wheel and gently
pry out.

5-24 Removing the Flat Tire and Installing the
Spare Tire
1. Use the wheel wrench to loosen all the wheel nuts.
Turn the wheel wrench counterclockwise to loosen
the wheel nuts. Don't remove the wheel nuts yet.
Position the jack under the vehicle. If the flat tire is
on the front of the vehicle, position the jack on the
frame behind the flat tire.
If the flat tire is on the rear of the vehicle, use the
jacking pad provided on the rear axle.
CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack, you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to fit the jack
lift head into the proper location before raising
the vehicle.