The pilot and the flight instructor were flying the multi-engine airplane in preparation for the pilot’s multi-engine practical test the following day. Prior to departing, the pilots thought that the airplane had a total of 65 gallons of fuel onboard based solely on their observations of the airplane’s cockpit fuel quantity gauges. The pilot specifically stated that the main fuel tanks indicated 1/2-full and the auxiliary fuel tanks indicated 3/4-full. They departed and began a series of maneuvers and scenarios, and neither pilot selected the auxiliary fuel tanks for that portion of the flight. After about 1.3 hours of flight time, and while on approach back to the departure airport, the pilot reported that at about 1,500 ft agl, the airplane began to lose altitude and he perceived that the airplane’s engines had lost power. Shortly after, the flight instructor took control of the airplane and they attempted to restore engine power. The flight instructor pitched for best glide and began to search for a suitable landing location. During the landing attempt on an interstate, the airplane contacted a passenger vehicle and came to rest between the center lanes of the highway. The airplane’s fuselage was substantially damaged during the accident sequence. Postaccident examination of the airplane revealed all of the fuel tanks were intact and the fuel caps remained secured. The cockpit fuel gauges indicated that both main fuel tanks were empty and that the right and left auxiliary fuel tanks contained 1/4 and 1/2 tank, respectively; a total of 23 gallons. About 1 pint of fuel was recovered from each of the main fuel tanks. Given this information, it is likely that the simultaneous loss of engine power to both of the airplane’s engines was the result of fuel starvation.