Automatic Transmissions do not work without fluid, nor do they work well without the correct fluid. Automatic Transmission Fluid (ATF) is one of the most complex of all lubricating fluids. It has to reduce friction enough to prevent wear and control temperature while at the same time allowing some friction to prevent the internal clutch material from slipping. This same fluid must operate at low and high temperature extremes. Rislone High Mileage Transmission Stop Slip with Leak Repair contains a special blend of viscosity improvers, anti-wear friction modifiers and extreme pressure performance additives to solve most transmission problems. These additives reduce rough shifting and friction, while eliminating slip, controlling temperature, and repairing shudder, chatter and whining. Excellent to use as a preventative maintenance product. Use to top off existing fluid when low or add a bottle when changing fluid. Specifically designed for higher mileage vehicles over 75,000 miles.