Exactly, the trucks are able to get better at emissions while keeping power and economy by combining EGR advancements along with new SCR technology which runs cleaner and traps more soot. The only downside is with the operators as catalyst filters need to be changed as often as every 50k miles which gets costly when…

Thanks for the response! Yeah, it seems like the tradeoff in diesel seems to be soot vs NOx. I imagine this plays out importantly in Euro vs US regs.

The trucks were able to pass the emissions tests because they were set to retard the timing during a city cycle like the one that the EPA ran when they tested them which produced lower combustion temperatures and resulted in lower NOx levels. Once the trucks started moving down the highway, the ECMs recognized that…