Large, heavy vehicles with high hoods and poor visibility are incredibly dangerous. Even people who drive them will admit that if they hit someone, that person would probably die. At the same time, though, people are selfish and want to look out for their families first. If they’re going to be in a wreck, they want to make sure the people inside their Pedestrian Crusher 9000 are as safe as possible. Except bigger doesn’t actually mean safer, as new research from the Insurance Institute for Highway Safety shows.
That said, there is a little bit of truth to the idea that larger vehicles are safer inside. Adding more weight to vehicles that weigh less than the fleet average did reduce the risk of a fatal crash, but only up to a certain point. Once a vehicle weighs more than the fleet average, you stop seeing notable decreases in fatalities as weight continues to increase. Meanwhile, adding weight to a vehicle that’s lighter than average didn’t make it more dangerous to people in other vehicles, while adding more weight to a vehicle that’s already heavier than average did.
Sadly, it doesn’t appear that this study looked at how adding weight to lighter vehicles impacted pedestrian safety, but that’s kind of understandable considering the researchers were focused on occupant safety. Plus, we already know F=MA, and when M goes up, so does F. Especially since humans haven’t evolved additional safety features recently like cars have.
“For American drivers, the conventional wisdom is that if bigger is safer, even bigger must be safer still,” IIHS President David Harkey said in a statement. “These results show that isn’t true today. Not for people in other cars. And — this is important — not for the occupants of the large vehicles themselves.”
This isn’t a new phenomenon for the IIHS to study:
IIHS has been studying crash compatibility — or how the interaction between different vehicles affects the relative safety of their occupants — for many years. For this update, researchers examined two-vehicle crashes that occurred between 1- to 4-year-old cars, SUVs and pickups. They looked at two periods, 2011-16 and 2017-22, and calculated driver death rates for vehicles and their crash partners per million registered vehicle years (i.e., one vehicle registered for one year).
In general, the researchers found that compatibility across vehicle types has continued to improve, a phenomenon that IIHS first documented in 2011 and analyzed most recently in 2019.
For many years, SUVs and pickups posed an outsize threat to people in cars, in part because their force-absorbing structures were not aligned. As a result, when an SUV or pickup struck a car, it bypassed the car’s crumple zone and rode up over the hood of the smaller vehicle.
Beginning in 2009, as part of a voluntary commitment that IIHS helped broker, automakers changed the front ends of their SUVs and pickups to make them align better with cars’ energy-absorbing structures. They also strengthened the structures of their cars and added side airbags to all varieties of vehicles to protect occupants in T-bone crashes.
Largely as a result of those changes, both SUVs and pickups are substantially less dangerous to people in cars than they were earlier.
When the IIHS says “substantially less dangerous,” it means it. Occupants in vehicles manufactured prior to automakers making those changes “were 90% more likely to die in crashes with SUVs weighing more than 5,000 pounds as in crashes with other cars.” Meanwhile, heavy SUVs built between 2017 and 2021 were only 20 percent more likely to kill the other occupants. So if you insist on buying something massive, at the very least get one that’s new enough not to be a giant safety hazard for others.
Large trucks were even worse than SUVs between 2011 and 2016. If you get hit by a truck, your odds of dying in that crash jumped 250 percent. Thankfully, the 2017-to-2022 data set showed that’s dropped significantly and is now a little below 200 percent. Wait, that’s still horrible, but hey, an improvement is an improvement, right? Fewer people dying when their car is hit by another driver is always a good thing.
Also, yes, if the lives of the people in the other car you hit don’t matter to you, then you are, in fact, a piece of shit. That’s not just my own personal belief, either. According to their scriptures, the Christian God agrees, and that covers, what, two-thirds of people in this country?
The average vehicle weight the IIHS used in the study was 4,000 pounds. Adding 500 pounds to lighter cars lowered the death rate by 17 deaths per million registered vehicle years while only increasing crash-partner deaths by one. Adding 500 pounds to a vehicle that’s already heavier than that average reduced driver deaths by one but increased crash-partner deaths by seven.
“There’s nothing magical about 4,000 pounds except that it’s the average weight,” Sam Monfort, a senior statistician with the IIHS and the study’s lead author, said in a statement. “Vehicles that are heavier than average are more likely to crash into vehicles lighter than themselves, while the reverse is true for vehicles that are lighter than average. What this analysis shows is that choosing an extra-heavy vehicle doesn’t make you any safer, but it makes you a bigger danger to other people.”
Unfortunately for all of us, vehicles are definitely getting heavier. IIHS found that the weight of the average car rose from 3,277 pounds in the 2011-2016 data to 3,308 pounds in the 2017-2022 data. As far as pickup trucks go, 97 percent now weigh more than 4,000 pounds, up from 91 percent in the old data set. That said, the proportion of SUVs that weigh more than 5,000 pounds did improve, dropping from 11 percent to 7.4 percent. So see? Not everything is getting worse. Only most things.
Everyone has different needs, and a car that works for one person often won’t work for another one, but at least we now know that even if you’re only concerned about the safety of the people inside your own car, there’s no significant benefit to buying something bigger and heavier at the expense of other people’s safety.