2017 Leisure Travel Vans U24TB 2017 Leisure Travel Vans U24TB An impressive feat of German Engineering, the Mercedes-Benz 3500 Sprinter Chassis is the perfect fit for the 2016 Unity by Leisure Travel Vans. And, with a three-liter V6 BlueTEC diesel engine under the hood, you'll enjoy a smooth yet powerful ride with class leading fuel economy estimated at 15 - 19 mpg. Whether you choose the queen-size Murphy bed, the walk-around island bed or even a double twin bed layout, you can be sure to find a Unity layout that fits your lifestyle.