Fluid is the key word in todays automatic transmission fluid market – fluid as in change. Driven by legislative mandates and developments in transmission design, ATFs have changed rapidly and dramatically the past few years. Part of what has happened is that better performance is being demanded of fluids – a trend that is familiar in motor oils and other corners of the lubricant industry. But its not just that standards have toughened. The number of standards in the market has increased, and complying with them is becoming procedurally more difficult, at least in some cases.