The (3V) 24 Valve 5.4L Triton motors for commonly produce distinctive rattling noises due to wear, most noise are normal but excessive ones calls for an inspection. The camshaft phasers, tensioners and the guides may fail over time. This is a complete kit manufactured by AA Ignition including the RTV gasket maker. Please note that if you do not align the camshafts correctly, your engine may suffer from serious damage as a result. Fits the following 5.4L 3 valve engines with 8th Vin Digit "5" : 2005-2008 Expedition 2004-2008 F-150 or 8th Vin Digit "V" 2005-2008 F-250 Super Duty 2005-2008 F-250 Super Duty 2006-2007 Mark LT 2005-2008 Navigator Replaces the following part numbers for each part: Camshaft Phaser Sprockets - 3R2Z 6A257-DA Phaser Bolts - 3L3Z 6279-DA Primary Chain Tensioner - XL1Z 6L266-AA Primary Chain Tensioner - 1L3Z 6L266-AA Timing Chain Guide - F85Z 6K255-AA Timing Chain Guide - 4L3Z 6M256-AA Timing Chain Guide - F85Z 6M274-AA Timing Chain Guide - 2L1Z 6K297-AA Lower One Piece Double Crankshaft Gear - XL3Z 6306-AA Front Crankshaft Seal - XW4Z 6700-AA Front Timing Cover Gasket - 3L3Z 6020-EA Front Timing Cover Gasket - 3L3Z 6020-FA Front Timing Cover Gasket - 3L3Z 6020-DA Timing Chains - 5L3Z 6268-A This is a compatible replacement part manufactured by AA Ignition. This variable camshaft timing kit is NOT a genuine OEM part. Vehicle makes and their associated vehicle models are registered trademarks of their respective owners. These trademarks and part numbers are used in this listing only to identify the vehicles this variable camshaft timing kit fits. AA Ignition is a registered trade mark of GWA Auto Parts Inc.