Hi,
We used to tow a Lunar Lexon with a '53 V70 D5 auto. Never had any mechanical problems with the car and it towed the 'van (1400kg) with ease. Used it regularly to go to the South of France, two adults and the usual caravan gear. We were very happy if we averaged 26 mpg towing, solo the best we ever got was 46 mpg, usually more like 38 mpg on a motorway run. Around town, low 30s. We traded to an E Class estate because the turning circle of the V70 was very poor and there was a paintwork issue which Volvo refused to rectify after the 3yr warranty.