Weight Class - Statistics show that if two vehicles with the same NHTSA full frontal rating crash into each other head on, but one vehicle weighs twice as much as the other, the occupants of the lighter one (2000 lbs / 909 kgs) are eight times more likely to be killed than the occupants of the heavier vehicle (4000 lbs / 1818 kgs).  However, vehicle weight offers no safety advantage or disadvantage in single-vehicle crashes.

Weight Class Categories

	3500 lbs / 1590 kgs or more
	3000-3499 lbs / 1363-1589 kgs
	2600-2999 lbs / 1181-1362 kgs
	2300-2599 lbs / 1045-1180 kgs
	Less than 2300 lbs / 1045 kgs

Keep in mind that crash test results shouldn't be compared among vehicles with large weight differences (more than 15%), so we have divided the vehicles into 5 distinct weight categories.  

The weight we use is the specific weight of the vehicle used in the  test that was conducted.  Very often a differently optioned vehicle will weigh 10% more or less than the weight we've assigned to it.  Please re-adjust the weight class category to meet the exact weight of your vehicle. Different engine, transmission, and accessory option packages can make a big difference.  The weight class rating for a any given model is not set in stone.

NHTSA released a new study in October of 2003 that further examines the differences in weight.

Weight reductions in passenger cars, lighter vans, pickup trucks, and sport utility vehicles (SUVs) increased the risk of fatal crash involvement, a study by the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) has concluded. The study of 1991-99 models also found that large four-door passenger cars and minivans had the lowest fatality rates of all vehicle types.

The study, done on the recommendation of the National Academy of Sciences, found that:

• Modest (100-pound) weight reductions in heavier (3,850 to 5,000 lbs.) light trucks and vans (LTVs) had little net effect on crash fatalities.
• Modest weight reductions in the heaviest LTVs (greater than 5,000 lbs.) were associated with a reduction in fatalities in other vehicles.
• One hundred-pound weight reductions in lighter LTVs and most passenger cars significantly increased fatality risk.
• Large 4-door passenger cars had the lowest fatal crash rates followed closely by minivans. The highest fatal crash rate was observed in small 4-door cars, mid-sized SUVs and compact pickup trucks.

Two factors accounted for the difference in fatal crash rates between large passenger cars (average weight 3,596 lbs.) and mid-sized SUVs (average weight 4,022 lbs.). Mid-sized SUVs were nine times as likely to involve a rollover fatality and twice as likely to cause a fatality in occupants of other vehicles. In non-rollover crashes, the fatality rate for the occupants of SUVs and passenger cars of similar weight was essentially equal.

The study examined fatality data from 1995-2000 involving 1991-1999 model vehicles. Researchers adjusted the data to account for differences in driver age and gender, rural versus urban driving and other variables such as nighttime driving.

The full study is available on the NHTSA web site at: http://www.nhtsa.dot.gov/cars/rules/regrev/evaluate/pdf/809662.pdf.

Occupant death rates in two-vehicle crashes, 1990-95 model passenger vehicles versus other vehicles ( deaths per million vehicles per year)
Weight Class (lbs)		Vehicle crash pairs 1990-1995
		Cars		Pick-ups		SUVs
		Cars	Other	Pick-ups	Other	SUVs	Other
	less than 2500	109	35			105	58
	2500-2999	83	43	89	88	54	75
	3000-3499	60	48	56	116	53	75
	3500-3999	53	57	52	115	37	92
	4000-4499	49	58	44	144	29	91
	4500-4999			45	169	29	110
	5000 +			38	181	25	112

(Of note, occupants of the lightest cars have dramatically higher death rates.  Also, most significantly from a safety point of view, heavy pickups and SUVs are associated with far higher death rates in the OTHER vehicle than in themselves, or than death rates caused by comparably heavy cars. ) 

(Source IIHS)