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Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixtureat the surge tank, but only when the
engine is cool.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight.
Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-12for
more information on
location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
5-28
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Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-77andWheel Replacement
on page 5-81for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-84.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear in ation pressures as shown on the tire and loading
information label. SeeLoading Your Vehicle on
page 4-56andIn ation - Tire Pressure on page 5-72,
for more information. Make certain that all wheel
nuts are properly tightened. See “Wheel Nut Torque”
underCapacities and Speci cations on page 5-122.
If your vehicle has the Tire Pressure Monitor (TPM)
system, the sensors will need to be reset after a
tire rotation is performed. See “TPM Sensor
Identi cation Codes” underTire Pressure Monitor
System on page 5-73.
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Notice:If you have a tire size other than P265/75R16,
LT265/75R16, P265/70R16 or P265/70R17 use tire
chains only where legal and only when you must. Use
chains that are the proper size for your tires. Install
them on the rear tires only.
Don’t use chains on the front tires.
Tighten them as tightly as possible with the ends
securely fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
If a Tire Goes Flat
It’s unusual for a tire to “blowout” 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 “blowout,” here are a few
tips about what to expect and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
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.
{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
If a tire goes at, the next part shows how to use your
jacking equipment to change a at tire safely.
5-83
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A. Push and Pull
B. Rotate Tire
7. Make sure the tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If the tire
moves, use the wheel wrench to tighten the cable.
Reinstall the spare tire lock (if equipped).To store the tools, follow these procedures:
For Yukon, do the following:
1. Put the tool kit, with the jack tools and gloves, in
the tool bag and place in the retaining clip above
the jack.
2. Tighten down with the wing nut.
3. Then, assemble wheel chocks and bottle jack
together with the wing nut and retaining hook.
4. Position behind the jack storage cover in the left
rear side panel and tighten, adjusting clockwise
until the jack is secured tight in the mounting
bracket. Be sure to position the holes in the base of
the jack onto the pin in the mounting bracket.
For Yukon XL, do the following:
1. Return the tool kit (jack tools and gloves) to the
tool bag.
2. Assemble wheel chocks and bottle jack together
with the wing nut and retaining hook.
3. Position under the jack storage tray in the left rear
side panel below the wheelbase and tighten,
adjusting clockwise until the jack is secured tight in
the mounting bracket. Be sure to position the
holes in the base of the jack onto the pin in the
mounting bracket.
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4. Use the retaining clip to fasten the tool kit on the
stud in the storage compartment in the rear left
trim panel and turn the wing nut clockwise to
secure.
5. Return the storage tray.
A. Tool Kit with Jack
Tools and Gloves
B. Retaining Bracket
and Wing NutC. Wing Nut Holding
Tire Blocks
D. Tire Blocks
E. Bottle JackA. Bottle Jack
B. Wheel Blocks
C. Wing Nut Holding
Tire Blocks
D. Mounting BracketE. Removable Tray
F. Retaining Hook
G. Retaining Bracket
and Wing Nut
H. Tool Kit with Jack
Tools and Gloves Yukon (Rear Access Panel)
Yukon XL
5-98
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4. Repeat this procedure at least two times. If the
spare tire lowers to the ground, continue with
Step 5 of “Removing the Spare Tire and Tools”
earlier in this section.
5. Turn the wrench counterclockwise until
approximately six inches (15 cm) of cable is
exposed.
6. Stand the wheel blocks
on their shortest ends,
with the backs
facing each other.7. Place the bottom edge of the jack on the wheel
blocks, separating them so that the jack is
balanced securely.
5-100
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