A shake-up in how vehicles are categorised for insurance purposes could well
mean that 4x4 drivers will pay more for their insurance.

For the first time, the Association of British Insurers (ABI) is taking into
account how much a car weighs to determine its insurance group.

It's not environmental reasons that are driving the changes, though -
instead, insurers reckon the heaviest models are the most likely to cause
severe third party damage in collisions.

http://www.whatcar.com/news-article.aspx?NA=224382