2005 GMC SIERRA spark plugs

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.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication Number
(VIN) on page 5-120.If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel on page 5-6. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.
Only vehicles that have the 5.3L V8 engine (VIN Code Z)
may use 85% ethanol fuel (E-85). General Motors
encourages the use of E-85 in vehicles that are designed
to use it. The ethanol in E-85 is a “renewable” fuel,
meaning it is made from renewable sources such as corn
and other crops.
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://www.afdc.doe.gov/refueling_mapsite.shtml) that
can help you nd E-85 fuel. Those stations that do have
E-85 should have a label indicating ethanol content.
Do not use the fuel if the ethanol content isgreaterthan
85%. Your vehicle may not operate properly if the
ethanol content is greater than 85%.
5-8

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)
Allison Transmission
®only: Change
automatic transmission uid and lter
(severe service).See footnote (m).••••••
Allison Transmission
®only: Change
automatic transmission uid and lter
(normal service).•••
Except Allison Transmission
®: Change
automatic transmission uid and lter
(severe service).See footnote (h).•••
Except Allison Transmission
®: 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.•
6-7

Normal Maintenance Replacement Parts
Replacement parts identied below by name, part number, or specication can be obtained from your GM dealer.
Part GM Part Number ACDelco®Part Number
Engine Air Cleaner/Filter
High Capacity
Standard25313348
25313349A1519C*
A1518C
Oil Filter
4300 V6
4800 V8; 5300 V8; 6000 V8
8100 V825010792
88984215
25324052PF47
PF46
PF454
Spark Plugs
4300 V6
4800 V8; 5300 V8; 6000 V8
8100 V825162556
12571164
1257827741–932
41–985
41–983
Wiper Blades (ITTA Type)
22 inches (56.0 cm)15153642 —
*A1518C high-capacity air cleaner lter may be substituted.
6-17