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 472for additional information.
California Fuel
If your vehicle is certi ed to meet California
Emissions Standards, it is designed to operate on
fuels that meet California speci cations. See the
underhood emission control label. If this fuel is not
available in states adopting California emissions
standards, your vehicle will operate satisfactorily on
fuels meeting federal speci cations, but emission
control system performance may be affected. The
malfunction indicator lamp may turn on and your
vehicle may fail a smog-check test. SeeMalfunction
Indicator Lamp on page 258. If this occurs, return to
your authorized GM dealer for diagnosis. If it is
determined that the condition is caused by the type
of fuel used, repairs may not be covered by your
warranty.
471
Fan and Drive:
Removal of fan clutch, if the vehicle has one,
or rendering clutch inoperative.
Removal of the fan shroud, if the vehicle
has one.
Air Intake:
Removal of the air cleaner silencer.
Modi cation of the air cleaner.
Exhaust:
Removal of the muffler and/or resonator.
Removal of the exhaust pipes and exhaust
pipe clamps.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 541.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas
inside and can burst if you drop or
scratch the bulb. You or others could be
injured. Be sure to read and follow the
instructions on the bulb package.
532
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for
wear and cracking. SeeScheduled Maintenance
(Gasoline Engine) on page 617for more
information.
Replacement blades come in different types and
are removed in different ways. For proper type and
length, seeNormal Maintenance Replacement
Parts (Gasoline Engines) on page 632.To replace the windshield wiper blade assembly
do the following:
1. Lift the wiper arm away from the windshield.
2. Push the release lever (B) to disengage the
hook and push the wiper arm (A) out of the
blade (C).
3. Push the new wiper blade securely on the
wiper arm until you hear the release lever
click into place.
542