All other things being equal, a heavier vehicle will generally better protect you in a crash. This is particularly the case in two-vehicle crashes.

National Highway Traffic Safety Administration (NHTSA) research historically has shown that occupants in passenger cars are at a greater risk of being fatally injured when struck in the front or the side by a heavier and higher-riding light truck (such as a pickup) or SUV. Improved energy-absorbing front ends and safety technologies such as head-protecting side-impact air bags can help lower this risk to vehicle occupants.

Source: National Highway Traffic Safety Administration (NHTSA) and www.safercar.gov