Using Lucas Fuel Treatment and Oil Stabilizer in four cars. ’99 Pontiac Bonneville went from c-20 mpg to 28+ mpg. ’03 Pontiac Vibe from 27 mpg to 35 mpg. ’03 Mitsubishi Gallant from 24/27 mpg to 32/35 mpg. ’89 Honda Civic with JDM 1600 V-tech from 24/28 mpg to 37 mpg. All cars very noticeably smoother, quiter. Honda ditto but with astonishing improvement in cold starting and running! Will be switching now to ALL Lucas products including transmission fluid. Great Products that actually work as claimed.