It depends on you. I personally like Castrol 10W40
The 1998 Ford Expedition Owner Guide shows ( 5W-30 )
According to the 1999 Ford Expedition Owner Guide ( 5W-30 )
The ( 1997 ) Ford Expedition Owner Guide shows ( 5W-30 )
5 w 20 ( according to the 2001 Ford Expedition owners manual )
( 5W-20 ) is the recommended oil , according to the 2002 Ford Expedition Owner Guide
( 5 w 30 ) according to the owners manual
5W-30 ( according to the 1999 Ford Expedition Owner Guide )
According to the 2002 Ford Expedition Owner Guide ( 5W-20 )
Valvoline Synthetic high mileage is what i use in my Expedition and F-150. Both over 100,000 miles.
On a 2000 Ford Expedition : The type of automatic transmission fluid to use should be engraved into the dipstick or on the dipstick handle
( 5 W 20 ) - according to the 2005 Ford Expedition owners manual
According to the 1999 Ford Expedition Owner Guide : With engine oil filter change : ( 6.0 U.S. quarts / 5.7 litres of 5W-30 ) * 5W-30 is used year round