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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 299
{ WarningWARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
HANDLING. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition
65 Warning 0 277 and the back
cover.
Vehicle Storage
{ Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
(Continued) Warning (Continued) not careful. See Jump Starting -
North America 0 351 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative ( − ) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative ( − ) cable from the
battery or use a battery trickle
charger.
Four-Wheel Drive Transfer Case
When to Check Lubricant
Refer to Maintenance Schedule
0 370 to determine when to check
the lubricant. How to Check Lubricant
Automatic Transfer Case
1. Fill Plug
2. Drain Plug
To get an accurate reading, the
vehicle should be on a level
surface.
If the level is below the bottom of
the fill plug (1) hole, located on the
transfer case, some lubricant will
need to be added. Add enough
lubricant to raise the level to the
bottom of the fill plug (1) hole. Use
care not to overtighten the plug.
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 351instructions on how to remove,
install, or store a spare tire, see Tire
Changing 0 342 .
If equipped with a temporary use
full-size spare tire, it is indicated on
the tire sidewall. See Tire Sidewall
Labeling 0 322 . This spare tire
should not be driven on over
112 km/h (70 mph), or 88 km/h
(55 mph) when pulling a trailer, at
the proper inflation pressure. Repair
and replace the road tire as soon as
it is convenient, and stow the spare
tire for future use.
CautionIf the vehicle has four-wheel drive
and a different size spare tire is
installed, do not drive in
four-wheel drive until the flat tire
is repaired and/or replaced. The
vehicle could be damaged and
the repairs would not be covered
by the warranty. Never use
four-wheel drive when a different
size spare tire is installed on the
vehicle. The vehicle may have a different
size spare tire than the road tires
originally installed on the vehicle.
This spare tire was developed for
use on this vehicle, so it is all right
to drive on it. If the vehicle has
four-wheel drive and a different size
spare tire is installed, drive only in
two-wheel drive.
After installing the spare tire on the
vehicle, stop as soon as possible
and check that the spare tire is
correctly inflated.
Have the damaged or flat road tire
repaired or replaced and installed
back onto the vehicle as soon as
possible so the spare tire will be
available in case it is needed again.
Do not mix tires and wheels of
different sizes, because they will not
fit. Keep your spare tire and its
wheel together. If the vehicle has a
spare tire that does not match the
original road tires and wheels in size
and type, do not include the spare in
the tire rotation. Jump Starting Jump Starting - North
America For more information about the
vehicle battery, see Battery - North
America 0 298 .
If the vehicle's battery has run
down, you may want to use another
vehicle and some jumper cables to
start your vehicle. Be sure to use
the following steps to do it safely.
{ WarningWARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
(Continued)
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 353Caution (Continued)warranty. Whenever possible, turn
off or unplug all accessories on
either vehicle when jump starting.
3. Turn the ignition off on both
vehicles. Unplug unnecessary
accessories plugged into the
accessory power outlets. Turn
off the radio and all the lamps
that are not needed. This will
avoid sparks and help save
both batteries. And it could
save the radio!
4. Open the hood on the other
vehicle and locate the
positive (+) and negative ( − )
terminal locations on that
vehicle.
The positive (+) terminal is
under a red plastic cover at the
positive battery post. To
uncover the positive (+)
terminal, open the red plastic
cover. For more information on the
location of the remote
positive (+) and remote
negative ( − ) terminals, see
Engine Compartment Overview
0 280 .
{ WarningAn electric fan can start up even
when the engine is not running
and can injure you. Keep hands,
clothing, and tools away from any
underhood electric fan.
{ Warning
Using a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
(Continued) Warning (Continued) your eyes or on your skin, flush
the place with water and get
medical help immediately.
{ WarningFans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
5. Check that the jumper cables
do not have loose or missing
insulation. If they do, you could
get a shock. The vehicles
could be damaged too.
Before you connect the cables,
here are some basic things you
should know. Positive (+) will
go to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative ( − )
will go to a heavy, unpainted