PACKAGE INCLUDED 16 x Hydraulic Roller Lifters 4 x Guide Trays FIT FOR Fit for LS1, LS2, LS3, LS6, LS7, LS9 LSX Engines (4.8L, 5.3L, 5.7L, 6.0L, 6.2L) For 1999-2002 Camaro and Firebird For 2010-2013 Camaro For 1999-2013 Corvette For 2004-2006 Pontiac GTO For 2004-2007 Cadillac CTS-V For 2008-2009 Pontiac G8 For 2000-2013 Tahoe, Yukon, Escalade For 2003-2009 H2 Hummer For 1999-2013 Silverado and Sierra (4.8L, 5.3L, 6.0L) INSTALLATION 1.Please check if the engine oil is clean enough; 2.Before installing the hydraulic tappet, it should be diffused in the oil; 3. Use your fingers to test the support seat in the center of the hydraulic tappet, and select those that are strong and have no subsidence and subsidence for installation. 4. When installing, try to prevent the oil from overflowing from the inner cavity of the hydraulic tappet; 5. If the air still enters the hydraulic tappet and causes noise, please follow the "Exhaust Procedure" to eliminate the noise . 6.Do not try to rotate the camshaft during installation, if it is really unavoidable, it should be reduced to the minimum extent possible; 7. When it is necessary to rotate the camshaft, it should be continuously rotated as much as possible, and do not perform a single stop-and-stop action. Stop at a different position each time; 8. Before starting the engine, the oil refilling procedure should be performed as much as possible to reduce the chance of air entering the hydraulic tappet.