The 2004 Mercury Mountaineer is available as a 4-door, 7-seat sport utility. Starting at $29,350, the 2004 Mercury Mountaineer 4.0L V6 Convenience (100A) 4x2 is powered by a 4.0L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 16-mpg in the city and 21-mpg on the highway. The top of the line 2004MercuryMountaineer4.6L V8 Premier (325A) AWD , priced at $ 38,335 , is powered by a 4.6L , 8 - cylinder engine mated to an automatic transmission that returns an EPA estimated 14-mpg in the city and 19-mpg on the highway.