If your vehicle has begun to misfire, idle erratically, or hesitate under acceleration a bad coil pack could be to blame. By providing the proper spark to the spark plug all of these running issues can be resolved. Made by an original equipment supplier (OEM) these coil packs surpass the factory quality and will get your engine running how it should be; smooth and fast. Please verify that your coils are square type and looks exactly like the ones pictured Fits the following V8 vehicles: 2002-2006 Escalade, Escalade EXT 2003-2006 Escalade ESV 2002-2006 Avalanche 1500 2003-2006 Avalanche 2500 2001-2002 Express 3500 1999-2006 Silverado 1500 2007 Silverado 1500 Classic, 1500 HD Classic, 2500 HD Classic, 3500 Classic 2001-2006 Silverado 1500 HD, 2500 HD, 3500 1999-2004 Silverado 2500 2000-2006 Suburban 1500 & 2500, Tahoe 2003-2006 Savana 1500 2003-2007 Savana 2500 2001-2007 Savana 3500 1999-2006 Sierra 1500 2007 Sierra 1500 Classic, 1500 HD Classic, 2500 HD Classic, 3500 Classic 2001-2006 Sierra 1500 HD, 2500 HD, 3500 1999-2004 Sierra 2500 2000-2006 Yukon, Yukon XL 1500 & 2500 2003-2007 H2 2004-2005 FasTrackFT1061, 1461, 1601, 1801 2005 FasTrackFT1261 Replaces part numbers: 12558693, GN10298, UF271, 52-1618, 5C1083, C1208, D581, E226 This is a compatible replacement part manufactured by AA Ignition. This ignition coil set is NOT a genuine OEM part. Vehicle makes and their associated vehicle models and part numbers are used in this listing only to identify the vehicles this ignition coil set fits.