Cars in the US are getting older: According to IHS, the average age for all US light vehicle in 2015 was 11.5 years . Cars are lasting longer, and this is a great thing if you own a car. This seems to have several causes: vehicles are being made better, the 2008 recession hit a lot of folks financially, and the average American is getting poorer .
For sale: 1999 Toyota Sienna Van. Needs work. $1400 OBO?
The ABS unit on my van needed replacement. When I brought it to the shop, the mechanic said he couldn't fix it - I should take it to the dealer. The dealer was happy to charge me $2400 - almost double the net worth of the car. I said "No thanks" and drove home. I'd bought the car new in 1999, and it still mostly runs. My kids had grown up in this car, shuttled around between activities, and finally learning to drive it.
There's always a "final straw" that makes a car not worth fixing. Maybe that's a wreck, or maybe an ABS brake unit, or maybe even a worn out tire.
"Every car in the junk yard is there because of one thing." - Car talk
|Average age of US cars and light trucks. Note y-axis scale starts at “9 years” to show slight differences by year.||Data: Polk.|
Pollution. Older cars pollute more for several different reasons. One Canadian study indicates that 25 percent of cars cause 90 percent of pollution . This is due to poorly tuned engines - more common in older vehicles. In California there is an effort to improve air quality by scrapping the oldest cars on the road. This program buys and scraps cars built in 1984 and earlier that have poor emission controls.
Not that simple: How much pollution does building a new car cause? It's a complicated question. You have to include mining, transportation, materials costs, and a lot of other factors. Pollution comes in many forms - destruction of land, toxic chemicals, and CO2 emissions. Of these, CO2 is the easiest to quantify, so we'll look at CO2 pollution.
Manufacturing a medium sized car emits around 17 metric tons of CO2 . Given that the average car produces 4.7 metric tons  of CO2 per year, manufacturing a car is worth 3 1/2 years of CO2 emissions. Of course that's an "average" car - old clunkers probably emit a lot more! This picture is further blurred when you look at the social benefits of auto manufacturing (jobs) and the non CO2 pollution created. Still, getting rid of the worst clunkers is a good idea.
Scrap of fix?
I took the old van to another mechanic (Meltons in Durham) and they gave me an estimate of $700 to fix it. The guy there said it's still a good car, and worth fixing. What was the environmental side of this choice? If I sold it, it would probably stay on the road for another few years. Since the engine is in good shape, it's probably not one of the worst polluters. Anyways, I only drive it a couple of thousand miles a year., and insurance costs are low.
Decision: Fix it.
 Average Age of Light Vehicles in the U.S. Rises Slightly in 2015 to 11.5 years
 The Average American Family Is Poorer
 Study suggests 25% of cars cause 90% of pollution
 Old Car Buyback
 What's the carbon footprint of ... a new car?
 Tons of CO2 per year