Subject: | Information on New Spark Plugs and Gapping |
Models: | 2004 Buick Rainier |
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, SSR, 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 |
2004-2005 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) |
Attention: | Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACDelco® Iridium Spark Plug Box. The statement will be removed from the boxes in the future. |
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard Corporate Bulletin Number 03-06-04-060A (Section 06 -- Engine/Propulsion System).
• | 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 1.01 mm (0.040 in) when the spark plug is made. |
Notice: 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. |