NEW YORK (CNNMoney.com) -- Ford issued the largest single recall in its history Tuesday as drivers of an additional 4.5 million vehicles were alerted about a fire hazard from a faulty switch.

The faulty switch can leak hydraulic fluid, overheat, smoke and then burn, and risks causing a fire even when the ignition is turned off, parked and unattended, the NHTSA said. [Details]