In the case of the DEF it absolutely reduces the lifespan of the engine. A truck engine that could last 500K miles lasts 200K max.
Factor a second or third engine (whole new truck) and the energy and pollution to produce it and DEF looks not as great.
Vehicles and engines that last 25 years are easy to build yet they are rare outside of commerical and military.
The whole argument is disengenuous and proceeds from an unstated a priori desire by government to restrict movement of citizens and markets, rather than as a real requirement for a real benefit.
Commercial fleet and military engines do not 'last' 25 years. They have a consistent maintenance schedule to fix and replace common wear parts. You have to think of it much more like the Ship of Theseus and not the same vehicle.
My last two vehicles lasted over 250k each, well, one is still going, I just don't own it any more. I feel the engine on the Toyota thats still running may last forever. It's replacing other parts outside the drive train that made it not worth it. Consumers are much more into toss and replace than full rebuild maintenance schedules.
I am not sure why you so casually dismissed this complaint without doing a quick search.
The whole reason why DEF is used[0] is because it reduces nitrous oxides, which are thought to be a pollutant.
Whether they actually are an effective greenhouse gas or not is probably a completely different thing we could argue about, but what is undisputed is the mechanism of action in the hot catalytic converter during engine operation, since it's the entire point of using the DEF in the first place.
In the catalytic converter, the urea thermally decomposes[0] to form Ammonia and Isocyanic acid[1], which is "a colourless, volatile and poisonous substance, with a boiling point of 23.5 °C".
23.5C is 74.3F. So, basically at room temperature the isocyanic acid becomes vapor. On a hot day, it vaporizes quickly and all that isocyanic acid has to go somewhere.
This is nasty stuff[2].
Anyway, the EPA probably figures that poisoning someone who's operating a diesel serves you right in order to reduce nitrous oxides. I've operated other diesels that are pre-DEF and never got sick like that.
There is no reason you should be exposed to volatile compounds from a normal parked rental truck. I would have asked for another truck or avoided U-Haul altogether.
Agreed. It was actually another national moving truck rental brand (not U-haul, I was just using it as a generic descriptor). I don't know why I'm not mentioning it since it seems like there's only a few national brands, but it's not their fault they have to use DEF and the truck was really great otherwise.
Factor a second or third engine (whole new truck) and the energy and pollution to produce it and DEF looks not as great.
Vehicles and engines that last 25 years are easy to build yet they are rare outside of commerical and military.
The whole argument is disengenuous and proceeds from an unstated a priori desire by government to restrict movement of citizens and markets, rather than as a real requirement for a real benefit.
It's all so tiresome...