Product updated on 2019-05-17, Zone Offroad - ZON:C1202, 2001 to 2006 Silverado and Sierra 2500 / 3500 2 inch leveling Torsion Bar Keys, Fits 2001 to 2010 Chev GMC Full size truck - Notes These keys will fit trucks with one of the following RPO codes : FT2-FT3-FT4-FT5-FT6-FT7. You can find the RPO codes in the glove box,