2008 GMC YUKON XL coolant level

3. Fill the coolant surge tank with the proper mixture,
to the FULL COLD mark.4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the
coolant is cold. If necessary, repeat coolant ll
procedure steps 1 through 6.
5-38

Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill the washer uid tank only three-quarters full
when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-14for
the location of the
reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down. The rst is that the
brake uid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
the uid level goes back up. The other reason is
that uid is leaking out of the brake hydraulic system. If
it is, you should have the brake hydraulic system
xed, since a leak means that sooner or later the brakes
will not work well.
5-41

ApplicationCapacities
English Metric
6L90-Transmission 6.3 qt 6.0 L
Transfer Case Fluid 2.0 qt 1.9 L
Wheel Nut Torque 140 lb ft 190Y
†Oil lter should be changed at every oil change.
After rell, the level must be rechecked. Add enough engine coolant so that the uid is within the proper operating
range.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
4.8L V8 C Automatic 0.040 in (1.01 mm)
5.3L V8 Flexible Fuel with
Active Fuel Management™
(Iron Block)0 Automatic 0.040 in (1.01 mm)
5.3L V8 Flexible Fuel with
Active Fuel Management™
(Aluminum Block)3 Automatic 0.040 in (1.01 mm)
5.3L V8 with Active Fuel
Management™ (Iron Block)J Automatic 0.040 in (1.01 mm)
6.0L V8 (Iron Block) K Automatic 0.040 in (1.01 mm)
6.0L V8 with Active Fuel
Management™
(Aluminum Block)Y Automatic 0.040 in (1.01 mm)
5-125

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-15. Reset oil life system.
SeeEngine Oil Life System on page 5-18.An Emission Control Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter on page 5-19.See footnote (l).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-78and “Tire Wear Inspection” inAt Least Once a Month on
page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid
as needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
6-5

(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
fittings, and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-62andWindshield, Backglass, and Wiper
Blades on page 5-113 for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any
other loose or damaged safety belt system parts. If you
see anything that might keep a safety belt system
from doing its job, have it repaired. Have any torn or
frayed safety belts replaced. Also see Checking
the Restraint Systems on page 1-92.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks, and folding seat hardware. More
frequent lubrication may be required when exposed to
a corrosive environment.Applying silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better, and
not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-28
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Inspect system. Check all fuel and vapor lines and
hoses for proper hook-up, routing, and condition. Check
that the purge valve works properly, if equipped.
Replace as needed.
6-8

(l)If you drive regularly under dusty conditions, inspect
the filter at each engine oil change.
(m)Visually inspect belt for fraying, excessive cracks,
or obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-15.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-28.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
6-9