Sir, David Duffy (Motoring, June 16) is going against common sense and the available data if he suggests criticism of large 4x4s is unwarranted and goes on to promote driving them in Oxford. The use of these vehicles as an urban runabout is selfish consumerism of the worst order. To suggest that fuel consumption is similar to an equivalent saloon car is nonsense.

4x4s are robustly constructed and have mechanicals designed for use off-road, all of which adds up to heavy vehicles requiring especially powerful engines that inevitably use more fuel. A diesel MPV offering a similar performance and the same number of seats will typically use nearly a gallon less for each 100 miles travelled and emit correspondingly less CO2. Further, in the event of an accident, tests prove that the extra weight, combined with a 4x4's additional height and bulk, increase the vulnerability of pedestrians, cyclists and small cars. Leave the 4x4s to those who actually need its towing or off-road capabilities.

Paul Davies, Oxford