only the old old old jalopy diesels a lot of people are still driving that don't have particle filters.
I kid you not, I was behind a Dodge 2500 pickup yesterday at a light that had a huge CUMMINS sticker on the back
and when the light turned green, the sky turned black.
Also have the twin vertical exhaust stack trucks, semi truck style. At least they spew upward.
In the intermountain west here, it is still "cool" to blow black smoke.
Pretty nice present Morticai, wow. New cars are spendy.
I am still looking for a old VW diesel pickup that has round headlights.
Cheers to the new diesel engines,
too bad we cannot get them all here in the States.