It probably depends on the kind of journeys you'll use the car for when you're not towing your caravan. If you cover a lot of long journeys, don't be quite so quick to ditch the diesel. A hybrid would be better for short journeys or urban use, however, and many will be more than up to the job of towing 1,350kg. Take a look at the Toyota RAV4. The AWD hybrid model has an official braked towing capacity of up to 1,650kg capacity, while the plug-in variant can tow up to 1,500kg.