An insurance group says low-speed crashes result in expensive repairs simply because of differences in the bumper height between cars and sport utility vehicles.

The Insurance Institute for Highway Safety tested five pairs of 2004 and 2005 vehicles from major car companies, putting each through 10 mph crash tests against each other. The SUVs and smaller cars were matched up based on maker.

It found cars from Ford had the lowest repair costs. Cars made by Volvo and Daimler Chrysler AG had the highest repair costs.

When Ford's Taurus crashed into an Explorer, the damage totalled more than $2,600. It was $1,256 when the vehicles were reversed.

With the smaller car coming from behind, the Volvo S40 ramming the XC90 caused the most damage -- more than $6,000.

In testing of SUVs hitting cars, the Jeep Grand Cherokee and Dodge Stratus ran up more than $6,100 in repair bills. (See how other pairs fared.)

The group said it was surprising to see how much damage a car could do to an SUV. There are no set standards for bumpers on SUVs, trucks and other such vehicles, which led the insurance group to say those vehicles often have flimsy bumpers or none at all.