Let's take a closer look at why today's vehicles are much heavier than their predecessors, why the extra pounds add costs to owning and driving a new vehicle, and what automakers are doing to reduce vehicle weight. There is an upside to the weight issue, and we'll discuss that too.

Mainstream vehicles such as the Honda Accord,Toyota Camryand the FordTaurus have gained hundreds of pounds-and in some cases up to 650pounds-in the past 20 years. Sport sedans like the BMW 3 Series,Mercedes-BenzC-Class, and the Audi A4 have also gained similar amounts-in some cases up to 550 pounds. And while the relatively lightweight Toyota Corollaand Honda Civicare still relatively small, they too have added hundreds of pounds to their curb weights due to consumer demand for safety, comfort and convenience features over the past few decades.

In general, there are two reasons why late-model cars are much heavier than their predecessors: safety and convenience.

Mandated Safety Features Add Mass
By law, modern vehicles are required to be fitted with a variety of safety-oriented technology (anti-lock brakes, stability control and tire-pressure-monitoring systems, etc.) and equipment (air bags,laminated glass, door intrusion beams, etc.). While these safety features are obviously welcomed they do add weight to the vehicle. In some cases, new systems and components are added; in other cases,existing parts are strengthened and reinforced to resist deformation of the body structure in a crash.

Comfort and Convenience Features Add Weight Too
Convenience features aren't new; cars have always been fitted with luxury items. But modern vehicles-even entry-level models-are typically fitted with an overflow of features that make driving easier and more convenient. Consumers today desire a full complement of power and luxury equipment (heated/cooled seats, sound deadening, rear climate control, etc.) as well as the latest technologies (Bluetooth connectivity, infotainment systems, real-time navigation, etc.). Again,the tradeoff for added convenience is weight-and in some cases, plenty it.