I might not agree with CARB, its methods, the restrictions or whatever. That said - it is very difficult to argue with the results. I spent several years in the 80’s commuting to Ontario and Redlands - to the east of LA. In the summer afternoons the smog was so bad - you could not see 100 yards, somtimes it was 100 feet - as in you could not see across the street. We were all breathing that junk. In LA proper - today most days you can see the Hollywood sign from El Segundo, which could never happen in the 80’s, 90’s, or 00’s. In Ontario/Redlands they don’t have those “sightless“ days any more - which doesn’t imply they are great.
Biodiesel is becoming popular because its cheaper than #2. Some of the large corps - 76 in particular - use B20, which makes them pop on GasBuddy and other apps. Like using ethanol, personally I think that and B20 are about feeding a special interest more $$. Given the resistance to a 2x maint schedule needed for B20 (like mine) - I don’t see it making much of a run here… Yes, older Semi’s are being outlaw’d, tho I don’t have the particulars… Next I think they’re going to get rid of fossil fuels for electric - completely. Fortunately, my progeny will have to deal with the disposition of my diesel Fords - I’ll be gone by then, and the trucks will still be running...
Here’s the fun fact… that EGR on my 2016 Scorpion - costs some 3 to 5 MPG… so I average 13.5 MPG no matter if I’m towing 10K or an empty truck (+18mpg in the 97 with the 7.3 - same roads and towing). The only time it gets better is on the freeway going slow, which I don’t. So, how does that +25% additional fuel consumption & MPG loss square up against the particulate savings?
Not trying to create a huge discussion of what is better or worse, we’ve already done that in 50 other threads. Just a note that I can complain about the restrictions all I want - I’ve personally seen the difference with and without the restrictions. Disclosure - I live around the 40th parallel… we don’t have that problem.