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.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS
is the only gasoline additive recommended by General
Motors.
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 speci cations 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.
5-8
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 only: Change
transfer case uid (severe service).
See footnotes (g) and (m).•••
Four-wheel drive only: Change
transfer case uid (normal service).
See footnote (g).•
Inspect evaporative control system.
An Emission Control Service.
See footnotes † and (k).•••
Replace spark plugs and inspect spark
plug wires.An Emission Control Service.•
Engine cooling system service (or every
ve years, whichever occurs rst).
An Emission Control Service.
See footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service.
See footnote (q).•
6-8
Maintenance Replacement Parts
Replacement parts identi ed below by name, part number, or speci cation can be obtained from your dealer/retailer.
If your vehicle has the DURAMAX
®diesel engine, see the DURAMAX®Diesel manual for more information.
Part GM Part Number ACDelco Part Number
Engine Air Cleaner/Filter
Standard Filter 15908916* A3086C*
High Capacity Filter 15908915 A3085C
Oil Filter
4.3L V6 25010792 PF47
4.8L V8; 5.3L V8; 6.0L V8; 6.2L V8 89017524 PF48
Spark Plugs
4.3L V6 12607234 41-993
4.8L V8; 5.3L V8; 6.0L V8; 6.2L V8 12609877 41-985
Wiper Blades – 21.6 in (55.0 cm) 25877402 —
*15908915 (A3085C) high-capacity air cleaner lter may be substituted.
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