Engine temp getting too high, or poor quality gas. Try some f/i cleaner and some octane boost.
On a 2001 Ford Explorer Sport Trac , 4.0 litre SOHC , V6 engine : With engine oil filter change : ( 4.7 litres / 5.0 U.S. quarts of 5W-30 engine oil )
The 2002 Ford Expedition has a V8 engine.
The 2002 Ford Taurus has a V6 engine.
The 2002 Ford Explorer has a V6 engine.
The 2002 Ford Mustang has a V6 engine.
The 2002 Ford Escape has an inline 4 engine.
The 2002 Ford Focus has an inline 4 engine.
The 2002 Ford F-150 has a V6 engine.
A 2002 Ford Explorer would have come from the factory with approximately a ( 192 * Fahrenheit engine cooling thermostat )
For a 2002 Ford Escort ZX2 ( in North America ) ( that would be the 2.0 litre , Dual Over Head Cam Zetec four cylinder engine )
On a 2002 Ford Ranger : The reservoir would be in the engine compartment There are reservoirs for brake fluid , windshield washer fluid , power steering fluid , engine coolant , etcetera
The 2002 Ford Expedition has a 4.6 L base engine size.