NHTSA Complaint #10763352 — 2007 TOYOTA PRIUS

I'M THE ORIGINAL OWNER AND DO MY OWN REGULAR OIL CHANGES AT THE MANUFACTURE SPECIFIED INTERVALS OF 5000 MILES. THIS LAST TIME I NOTICED NOT MUCH OIL COMING OUT OF THE DRAIN PAN, POURED IT BACK INTO AN EMPTY OIL JUG TO MEASURE AND YES ONLY 1.5 QUARTS DRAINED OUT. I HAVEN'T SEEN ANY SMOKE OR SMELLED ANY OIL BURNING AND NO OBVIOUS LEAKS. I DON'T RUN THE ENGINE HARD OR AT HIGH SPEEDS (LESS THAN HALF MY DRIVING IS INTERSTATE) BUT CAN'T FIGURE OUT WHY IT'S ALL OF A SUDDEN STARTED USING OIL. WHEN I SEARCHED ONLINE IT SEEMS TO BE A COMMON FAILURE WITH PRIUS OVER 100K MILES. I WANT TO ADD MY OTHER TOYOTA AND HONDA VEHICLES HAVE LASTED WELL OVER 200K AND 180K MILES WITH NO ENGINE TROUBLES AT ALL (I ALSO DO THE MAINTENANCE ON THEM)