marshall212 Report post Posted February 3, 2015 What is the difference between a Cat C7 and a 3126? Thanks Share this post Link to post Share on other sites
wolfe10 Report post Posted February 3, 2015 The C7 replaced the 3126. Basic engine the same. Major changes to fuel system and minor changes to other components to meet the much stiffer EPA emission requirements. The 3126 production ran roughly from 1996 to 2003. C7 2004 until production for on-highway engines ended in 2008 or so. Share this post Link to post Share on other sites
