I have always used Castrol Motor Oil in all my Vehicles. 10W30 or 10W40
( the Owner Guide shows 5W-30 is the preferred oil , that's what I have used in my 1995 Ford Explorer XLT for 15 years )
Ford uses the Motorcraft blended oil (part synthetic).
According to the 1999 Ford Explorer Owner Guide ( 5W-30 ) is used in all the engines
The motor oil drain plug is located on the motor oil pan.
5 W - 30 is the preferred oil for all 1998 Ford Explorer engines
SAE 5 W - 30 is the preferred oil , according to the 1996 Ford Explorer owners manual
5 w 30 , according to the 1999 Ford Explorer owners manual
Your 1991 Ford Explorer 4.0 liter takes 5 quarts ( 4.7 liters ) of motor oil WITH FILTER CHANGE
If you have the owner's manual, it usually says what kind of oil you need in there.
( 5W-30 ) according to the 1997 Ford Explorer Owner Guide
5W-30 is the preferred oil ( according to the Owner Guide )
5W-30 is the preferred oil according to the Owner Guide
( 5 w 20 ) for the 4.6 L - V8 in a 2003 Ford Explorer , according to the owners manual