2018 GMC YUKON XL octane

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
In Brief 25Loading Information label. See
Vehicle Load Limits 0 200 . The
warning light will remain on until the
tire pressure is corrected.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
may be an early indicator that the
tire pressures are getting low and
the tires need to be inflated to the
proper pressure.
The TPMS does not replace normal
monthly tire maintenance. Maintain
the correct tire pressures.
See Tire Pressure Monitor System
0 329 .
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure. See “ Tire Fill Alert (If
Equipped) ” under Tire Pressure
Monitor Operation 0 330 . Fuel (L83 5.3L V8 Engine) Regular Fuel
Use only unleaded gasoline rated
87 octane or higher in your vehicle.
Do not use gasoline with an octane
rating lower as it may result in
vehicle damage and lower fuel
economy. See Fuel 0 254 .
Fuel (L86 6.2L V8 Engine)
Premium Recommended Fuel
Use premium 93 octane unleaded
gasoline in your vehicle. Unleaded
gasoline with an octane rating as low as 87 may be used, but it will
reduce performance and fuel
economy. See Fuel 0 254 .
E85 or FlexFuel
FlexFuel Possible
Certain models are compatible with
E85 fuel. See E85 or FlexFuel
0 256 .
Engine Oil Life System The engine oil life system calculates
engine oil life based on vehicle use
and displays a DIC message when
it is necessary to change the engine
oil and filter. The oil life system
should be reset to 100% only
following an oil change.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
254 Driving and Operating .
Sudden lighting changes, such
as when driving through tunnels.
.
Banked roads.
.
Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.
A system unavailable message may
display if the camera is blocked.
The LKA system does not need
service.
LKA assistance and/or LDW alerts
may occur due to tar marks,
shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LKA off if these
conditions continue. Fuel GM recommends the use of TOP
TIER ®
detergent gasoline to keep
the engine cleaner and reduce
engine deposits. See
www.toptiergas.com for a list of TOP
TIER detergent gasoline marketers
and applicable countries.
If the vehicle has a yellow sticker on
the fuel door, E85 or FlexFuel can
be used. See E85 or FlexFuel
0 256 .
For the L83 5.3L V8 engine, use
regular unleaded gasoline meeting
ASTM specification D4814 with a
posted octane rating of 87 or higher. Do not use gasoline with a posted
octane rating of less than 87, as this
may cause engine knock and will
lower fuel economy.
For the L86 6.2L V8 engine,
premium unleaded gasoline meeting
ASTM specification D4814 with a
posted octane rating of 93 is highly
recommended for best performance
and fuel economy. Unleaded
gasoline with an octane rated as low
as 87 can be used. Using unleaded
gasoline rated below 93 octane,
however, will lead to reduced
acceleration and fuel economy.
If knocking occurs, use a gasoline
rated at 93 octane as soon as
possible, otherwise, the engine
could be damaged. If heavy
knocking is heard when using
gasoline with a 93 octane rating, the
engine needs service.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 255Prohibited Fuels
CautionDo not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:
.
For vehicles which are not
FlexFuel, fuel labeled
greater than 15% ethanol by
volume, such as mid-level
ethanol blends (16 – 50%
ethanol), E85, or FlexFuel.
.
Fuel with any amount of
methanol, methylal, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
.
Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(MMT), which can damage
the emissions control
system and spark plugs.
(Continued) Caution (Continued) .
Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and performance,
and may decrease the life of
the emissions catalyst.
California Fuel
Requirements If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance may be
affected. The malfunction indicator
lamp could turn on and the vehicle
may not pass a smog-check test.
See Malfunction Indicator Lamp
(Check Engine Light) 0 143 . If this occurs, return to your authorized
dealer for diagnosis. If it is
determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
Fuels in Foreign
Countries The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see “ Prohibited
Fuels ” in Fuel 0 254 .
Fuel Additives To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel 0 254 .
If TOP TIER detergent gasoline is
not available, one bottle of GM Fuel
System Treatment Cleaner added to
the fuel tank at every engine oil
change, can help. GM Fuel System
Treatment Cleaner is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.