Diesel Exhaust Fluid
In what year of diesel engine build was diesel exhaust fluid first required? Which engines for DP, prior to the exhaust fluid requirement, were considered good engines?
Forum Discussion
Earlier posts were wrong about the timing. There were two recent phases of emission reductions -- one starting in 2007, then another in 2010. It was the second of these (affecting engines manufactured starting in 2010) that most engine manufacturers met with a DEF system. Because of the lag between engines, chassis, and coaches, you could easily have a 2010 or even some 2011's with a 2009 engine, thus no DEF.
