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Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline. Also,
your dealer/retailer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specifications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.Notice:This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance
of the emission control system could be affected.
The malfunction indicator lamp might turn on. If this
occurs, return to your dealer/retailer for service.
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Four-wheel drive: Change transfer case
fluid (severe service).See footnotes (o)
and (p).•••
Four-wheel drive: Change transfer case
fluid (normal service).See footnote (o).•
Replace spark plugs and inspect spark
plug wires.An Emission Control Service.•
Engine cooling system service (or every
five years, whichever occurs first).
An Emission Control Service.
See footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service.
See footnote (n).•
Inspect evaporative control system.
An Emission Control Service.
See footnotes † and (k).•••
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Maintenance Replacement Parts
If the vehicle has the DURAMAX Diesel engine, see the DURAMAX Diesel manual for more information.
Replacement parts identified below by name, part number, or specification can be obtained by your dealer/retailer.
Part GM Part Number ACDelco Part Number
Engine Air Cleaner/Filter 15950115 A3097C
Engine Oil Filter
4.3L V6 25010792 PF47
4.8L V8, 5.3L V8, 6.0L V8 89017524 PF48
Spark Plugs
4.3L V6 12607234 41-993
4.8L V8, 5.3L V8, 6.0L V8 12621258 41-110
Wiper Blades — 22 in (56.0 cm) 25949887 —
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