spark plugs CHEVROLET SILVERADO 2004 1.G Owners Manual

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. You should not have to add anything to your
fuel. However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations. General
Motors recommends that you buy gasolines that
are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems due
to dirty injectors or valves, try a different brand
of gasoline.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
5-7

Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Except Allison: Change automatic
transmission uid and lter (severe
service).See footnote (h).•••
Except Allison: Change automatic
transmission uid and lter
(normal service).•
Four-wheel drive with automatic
transfer case only: Change transfer
case uid.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 5 years, whichever occurs rst).
An Emission Control Service. See
footnote (i).•
Inspect engine accessory drive belt.An
Emission Control Service.•
5-speed manual transmission only:
Change manual transmission uid.•
6-7

Normal Maintenance Replacement Parts
Replacement parts identied below by name, part number, or specication can be obtained from your dealer.
VIN Code W V T
Oil Filter 25010792**/PF47* 25010633**/PF44* 25010633**/PF44*
Engine Air Cleaner/Filter 25313348**/A1519C*† 25313348**/A1519C*† 25313348**/A1519C*†
PCV Valve 6487532**/CV769C* — —
Spark Plugs25162556**
/41–932*12571164**
41–985*12571164**
/41–985*
Wiper Blades 15153642** 15153642** 15153642**
Wiper Blade Type ITTA ITTA ITTA
Wiper Blade Length22 inches
(56.0 cm)22 inches
(56.0 cm)22 inches
(56.0 cm)
*ACDelco
®part number
** GM part number
†A1518C high-capacity air cleaner lter may be substituted.
6-16

VIN Code U N G
Oil Filter 25010633**/PF44* 25010633**/PF44* 89028862**/PF454*
Engine Air Cleaner
/Filter25313349**
A1518C*25313349**
A1518C*25313349**
A1518C*
PCV Valve — — —
Spark Plugs 12571164**/41–985* 12571164**/41–985* 12578277**/41–983*
Wiper Blades 15153642** 15153642** 15153642**
Wiper Blade Type ITTA ITTA ITTA
Wiper Blade Length22 inches
(56.0 cm)22 inches
(56.0 cm)22 inches
(56.0 cm)
*ACDelco
®part number
** GM part number
†A1518C high-capacity air cleaner lter may be substituted.
6-17