It’s a long-held belief that a bigger, heavier SUV means occupants are much more likely to survive a wreck. However, a recent study from the Insurance Institute for Highway Safety (IIHS) suggests that a full-size SUV with a weight of over 4,000 lbs doesn’t do much to increase your survival odds in a violent crash.  

A recent study suggests that a full-size SUV doesn’t mean a more survivable crash

The IIHS recently published a study that may change your mind about adding a 5,000-lb SUV to your driveway. For starters, the study found that vehicles weighing more than the fleet average enjoy substantially fewer increases in crash survivability with added weight.

So, adding an extra 500 lbs of girth to a full-size SUV that already outweighs the fleet average doesn’t do much to protect you better than a lighter model. Similarly, adding 500 lbs to a vehicle weighing more than the fleet average increases the likelihood of death for passengers in other vehicles. 

“For American drivers, the conventional wisdom is that if bigger is safer, even bigger must be safer still,” IIHS President David Harkey said on the subject. “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.”

The study also found that older-spec full-size SUVs and pickup trucks pose a greater risk to the occupants in other vehicles. With timeframes in consideration, the IIHS found that car occupants were around 90% more likely to die in a crash with 5,000-lb SUVs built between 2011 and 2016. Conversely, similarly heavy SUVs from 2017 to 2022 dropped that same likelihood to 20%.

“This analysis shows that choosing an extra-heavy vehicle doesn’t make you any safer, but it makes you a bigger danger to other people,” said Sam Monfort. Monfort was the lead author of the IIHS study and a senior statistician at the safety agency.