Industrial Injection GM Injector Line Set For 01-04 6.6L LB7 Duramax - 412501This is a complete set of brand new fuel lines for the 2001 2004 LB7 Duramax. We recommend ordering a set of these lines when purchasing new injectors. Through years of doing warranty work and working on these model trucks we have found that most contamination of the injectors after install is from the injector lines not being cleaned well enough or at all. These lines take a lot of abuse and doing a new set is a great insurance towards the life of