Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts,
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts,
and other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
If you want to do some of your own service work, you
will want to use the proper service manual. It tells
you much more about how to service your vehicle than
this manual can. To order the proper service manual,
seeService Publications Ordering Information on
page 7-14.Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-86.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-20.
Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle
can affect the air ow around it. This may cause
wind noise and affect windshield washer performance.
Check with your dealer before adding equipment to
the outside of your vehicle.
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Fuel
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System” in the DURAMAX®
Diesel Supplement.
For vehicles with gasoline engines, please read this.
Gasoline
The 8th digit of your vehicle identi cation number (VIN)
shows the code letter or number that identi es your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identi cation Number
(VIN) on page 5-124.
If your vehicle has the 5.3L V8 engine (VIN Code Z),
you may use either regular unleaded gasoline or ethanol
fuel containing up to 85% ethanol (E85); also see
Fuel E85 (85% Ethanol) on page 5-8. In all other
gasoline engines, use only regular unleaded gasoline.
Gasoline Octane
For all vehicles, except those with the 6.0L V8 engine
(VIN Code N), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you may notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, your engine needs service.If your vehicle has the 6.0L V8 engine (VIN Code N),
use premium unleaded gasoline with a posted
octane rating of 91 or higher. You may also use regular
unleaded gasoline rated at 87 octane or higher, but
your vehicle’s acceleration may be slightly reduced, and
you may notice a slight audible knocking noise,
commonly referred to as spark knock. If the octane is
less than 87, you may notice a heavy knocking
noise when you drive. If this occurs, use a gasoline
rated at 87 octane or higher as soon as possible.
Otherwise, you might damage your engine. If you are
using gasoline rated at 87 octane or higher and you hear
heavy knocking, your engine needs service.
Gasoline Speci cations
At a minimum, gasoline should meet ASTM
speci cation D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
General Motors recommends against the use of
gasolines containing MMT. SeeAdditives on page 5-7
for additional information.
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