How to Add Anti-Freeze to a 2003 Ford Focus

The 1998 Ford Focus was such a segment-making automobile, it’s almost hard to believe that it directly replaced the Escort. While a decent enough car in its time, the Escort’s chassis and engineering were refugees from the Reagan era. The Focus’ C170 platform, its engines and overall design weren’t just ready for the 21st century — they still felt modern more than a decade later when the C1 Focus replaced them. Changing out the antifreeze on a first-generation Focus isn’t difficult, but the refilling process is somewhat unique.

Things You’ll Need

  • Wheel chocks
  • Floor jack
  • Jack stands
  • Phillips-head screwdriver
  • Flat-head screwdriver
  • Funnel
  • 6.1 quarts Premium Cooling System Fluid or Extended Life Coolant

  • Park the car on level ground. Turn the heater control temperature on high, and the blower fan speed on low. Shut the engine down and allow it to cool completely. Chock the rear wheels and set the parking brake. Lift the front of the Focus with a floor jack and secure it on jack stands. Pop the hood, and remove the coolant expansion tank cap.

  • Crawl under the vehicle and remove the engine undershield if so-equipped; simply unscrew all nine fasteners with a screwdriver and remove the tray. Slide a drain pan under the driver side of the radiator and locate the circular, plastic radiator drain valve. You can find it on the lower-left corner of the radiator, facing the engine.

  • Open the drain valve using a flat-head screwdriver slotted into one of the "crosshair" grooves in the valve. Allow the radiator to drain completely, then close the valve. Reinstall the undershield and fasteners, and lower the car.

  • Locate the upper heater core hose; it’s the top rubber hose leading from the firewall to the engine. Loosen the hose clamp that holds the heater core line to the fitting on the engine, and carefully wiggle the line off the fitting. Hold the line up and insert a funnel into the end.

  • Slowly add the recommended coolant to the core through the line until coolant begins to trickle out of the fitting on the engine. When it does, put your thumb over the heater core line and quickly slip it onto the fitting on the engine. Slide the hose clamp down and tighten it.

  • Fill the radiator expansion tank up to the "MAX" mark, and install the coolant expansion tank cap. Start the engine and hold it at 2,750 rpm until it gets up to temperature. Wait for the fan to turn on and off twice, then shut the engine off.

  • Allow the engine to cool down; as it does, it will draw fluid in through the expansion tank tube to fill any voids in the motor. Check the tank fluid level, and top it off to the "MAX" mark.