Ford 2010 Explorer Sport Trac Owner's Manual page 272

Roadside Emergencies
3. Connect the negative (-) cable to the negative (-) terminal of the
assisting battery.
4. Make the final connection of the negative (-) cable to the ground stud
located toward the front of the vehicle (forward of the battery) on the
radiator support. Keep the negative (-) cable away from the battery and
the carburetor/fuel injection system.
272
2010 07+ Explorer Sport Trac (esp)
Owners Guide (own2002), 1st Printing
USA (fus)