<Tr> <Th> Predecessor </Th> <Td> Ford Bronco II </Td> </Tr> <P> The Ford Explorer is a range of SUVs manufactured by Ford Motor Company . Introduced in 1990 for the 1991 model year, it is currently in its fifth generation . It has been marketed through the Lincoln - Mercury Division as the Mercury Mountaineer (1997 - 2010) and Lincoln Aviator (2003 - 2005). As with the Ford Ranger, it derives its name from a trim package used on the Ford F - Series (from 1968 to 1986). Alongside it, Ford also markets the Ford Police Interceptor Utility, a replacement for the Ford Crown Victoria Police Interceptor . A specially modified Special Service Vehicle version is also available from Ford Fleet for law enforcement agencies, fire departments, and EMS agencies . </P> <P> Intended as the replacement for the Ford Bronco II, the Ford Explorer was introduced in both two - door (the Ford Explorer Sport, also sold as the 1991 - 1994 Mazda Navajo) and four - door body styles, with the latter being the first four - door Ford SUV . Following the 2002 introduction of the third - generation Explorer, the Ford Explorer Sport was discontinued after the 2003 model year . The Ford Explorer Sport Trac is a mid-size pickup truck based upon two generations of the four - door style from 2001 to 2010 . It was sold with several powertrain configurations . Along with two - wheel drive (rear - wheel drive 1991 - 2010; front - wheel drive 2011 - present), part - time four - wheel drive, and all - wheel drive are options . Since 1995, part - time four - wheel drive has been a' shift on the fly' system with full protection against being engaged at high speed . </P> <P> As with its Ford Bronco II predecessor, the initial versions of the Ford Explorer derived its chassis and powertrain from the Ford Ranger, sharing a common chassis through 2001 for the four - door (the Explorer Sport was shared this commonality through its 2003 discontinuation and the Explorer Sport Trac would do so through 2005). For the 2002 launch of the third - generation Explorer, the model was given a body - on - frame chassis distinct from the Ranger . For the fifth - generation 2011 Explorer, the model range was shifted to unibody construction and into the full - size segment . Though sharing a similar chassis as the Ford Flex and Ford Taurus, Ford officially markets the current Ford Explorer as an SUV, slotted between the unibody - chassis Ford Escape and body - on - frame Ford Expedition . </P>

When did ford explorer change to front wheel drive
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