On April 26, 1997, at 1433 hours Pacific daylight time, a Cessna T182, N5482N, was destroyed during a forced landing approximately 4 statute miles east of Hemet, California. The forced landing was precipitated by a loss of engine power during cruise. The private pilot and two passengers were seriously injured. The flight originated at Chiriaco Summit, California, on the day of the accident at 1330 for a planned flight to French Valley, California. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The pilot stated in his accident report that he had visually checked the aircraft fuel status prior to departure from French Valley airport and that he observed both wing tanks to be full, however, the left cockpit fuel gage indicated "empty" and the right gage indicated "1/4". During the postaccident inspection of the airframe and engine, both the left and right fuel caps were observed to be in place and properly closed. The fuel tank selector was in the "both" position and could be moved freely. There was no evidence to indicate an engine, flight control, or airframe malfunction. However, there was no evidence of any fuel in either fuel tank, fuel lines, or engine fuel strainer bowl. Also, there were no stained areas around the wing fuel caps to indicate that fuel had drained from the tanks after the forced landing occurred. The FAA inspector stated in the enclosed report that, according to the operator's fueling records, the aircraft, at the time of the accident, had been flown for 5.3 hours since the last refueling. Aircraft records indicated that four takeoffs and landings had been accomplished during that period. The aircraft pilot's handbook states that, when fully serviced, there is a total of 88 gallons of useable fuel onboard, and that the engine burns approximately 16 gallons per hour at normal cruise power settings. This would equate to a 5.5 hour maximum endurance if all time flown was at cruising altitude with one takeoff and landing included. During the inspection, both left and right fuel gages were connected to the aircraft's battery and the tank floats were cycled from their "empty" to "full" positions. With the floats in the full (up) position, both cockpit fuel gages indicated "full." When the floats were placed in the empty (down) position, both cockpit gages indicated "empty," and there was a smooth and linear transition of the fuel gages from full to empty as the tank floats were cycled from the full to the empty position. The float levers moved smoothly throughout their motion envelope and there was no apparent hysteresis in the gage indications associated with the direction of motion of the tank floats.