I don't know this to be fact, so take it for what it's worth... A simple allegory by a deranged man...
Out here is lovely California it
used to be that all diesels, regardless of the year, were smog exempt. Simply pay your tags (which average somewhere around $300 a year now for heavy "commercial" trucks such as ours, even though I have never hauled anything for hire in my life..) and be on your merry way.
For a while, everyone it seemed was happy. Diesel trucks were the perfect solution to Cali's absurd smog requirements.
That was, until the bombers arrived. They found a way to ruin this perfect loop hole. Every Ford/GM/Dodge diesel owner was chipped up, blacking out intersections, rolling coal. Obviously this
couldn't go on. This is California. This had to stop, and stop it did.
Very secretly, the C.A.R.B. (California Air Resources Board, think- Federal EPA on steroids with a crack pipe in one hand and the instrument of legislation in the other) managed to slip a couple clever little laws through...
One made it impossible to register heavy commercial diesel trucks older than a certain age (F-superduty and heavier) Literally, you can not have them on the road anymore. Period. End of the line. All IDI F-superduty trucks are officially illegal in Ca. now...
The other made it a requirement for ALL 1998 and newer diesels to have smog checks done bi-annually (just like the gas cars) except, as it would turn out, you can't simply hook a diesel up to a smog check machine or a dyno, can you? It would be way too expensive to require auto repair shops to buy diesel compatible test equipment... So, the requirement is that the guy certifying your truck does two things... One, they crawl all around your truck, "inspecting" for illegal devices (chips, bigger intakes, turbos, injectors, pumps, egr/cat deletes- you name it) if they find anything - FAIL. The second is they run the truck on a dyno (if they have one) and put it under load, while someone watches the tail pipe for "excessive smoke." Think about that one. How can you define "excessive smoke" it is entirely subjective to the eye of the guy watching your tailpipe. If his glasses are dirty, you pass. If he just cleaned his glasses, you FAIL....
As of now, lighter duty trucks (less than 15k gross I believe) are exempt here in CA. But who knows for how long? At one point I really believed in the status quo for smog requirements. That's changing. I forsee at some point it's going to be illegal to own older trucks and cars out here, except registered "antiques" or "classics" that have very strict restrictions on how and when you can drive them.
The more coal we roll the quicker this stuff happens. I would like to keep my older trucks on the road for as long as I can.
The end...
