Har gjort litt søk rundt plugger og fant at det er irridium som er OEM plugger til 4,8 - 5,3 og 6,0. Det var opprinnelig platinum plugger orginalt, med ACDelco pn. 41-952 med åpning på 0.060 inch. Denne er nå utgått og erstattet med ACDelco irridium pn. 41-985 med åpning 0.040 inch. Tenkte det var greit å poste dette, er jo så mange forskjellige plugger som står listet når man skal handle fra f.eks Rockauto, er fort gjort å kjøpe feil.
Her fra Cadillacforums:
<div>Ignition System Specifications
Application Specification Metric English
Firing Order 1-8-7-2-6-5-4-3
Spark Plug Wire Resistance 1000 ohms per ft
Spark Plug Torque 15 N·m 11 lb ft
Spark Plug Gap 1.52 mm 0.060 in
Spark Plug Type 25171803 [AC plug type]
12567759 [NGK plug type]
CutNpaste info from the service manual. There's also this TSB:
Information on New Spark Plugs and Gapping #03-06-04-060 - (Oct 24, 2003)
Information on New Spark Plugs and Gapping
2004 Buick Ranier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV
2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, TrailBlazer
1999-2004 GMC Sierra
2000-2004 GMC Yukon, Yukon XL
2001-2004 GMC Yukon Denali, Yukon XL Denali
2002-2004 GMC Sierra Denali
2003-2004 GMC Envoy XL
1998-2002 Pontiac Firebird
2004 Pontiac GTO
2003-2004 Hummer H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)
A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040 inches) when the spark plug is made. The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
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