If we knew that, we also might know why Ford doesn't have the economies of scale to spend the engineering time to get the SportTrac right in the first place, and why there are so many problems with:
transmissions,
power steering pumps,
alternators,
timing chains,
check engine lights,
wind noise,
bad handling,
vibration,
worn seat fabric,
seats that "rock",
lumbar supports that disintegrate,
tires that cup,
paint that discolors,
clearcoat that cracks,
hood insulation that falls apart,
rear windows that don't work,
horrible gas mileage,
radiator hoses that wear through,
clueless dealer service departments,
bad vacuum hose elbows,
wimpy shock absorbers,
inadequate anti-sway bars,
knocking engines,
etc.
etc.
etc.
etc.
etc.