I get 15.3 in my 2005.
According to the 2003 Mercury Mountaineer Owner Guide : ( DOT 3 brake fluid , meeting Ford specification ESA-M6C25-A )
That would be the 4.6 liter engine, which takes six quarts. * of 5W-20 according to the 2003 Mercury Mountaineer Owner Guide
( # 24 ) is a blue color 15 amp fuse for the cigarette lighter and OBD II in a 2003 Mercury Mountaineer ( under the instrument panel )
On a 2003 Mercury Mountaineer , 4.6 litre V8 engine : firewall 4 - 8 3 - 7 2 - 6 1 - 5 front of vehicle
only when it begins to fail.
According to the 2003 Mercury Mountaineer Owner Guide : In the fuse panel under the drivers side of the dash : ( # 24 is a 15 amp fuse for the cigarette lighter and OBD II )
5.0 quarts 4.7L ( of 5W-30 for the 4.0 liter V6 ) 6.0 quarts 5.7L ( of 5W-20 for the 4.6 liter V8 ) In a 2003 Mercury Mountaineer