FORD 2002 Taurus v.3 - Manual (Page 148)

(Overdrive)
The (Overdrive) position is the
normal driving position for an
automatic overdrive transaxle.
When in the (Overdrive)
position, the transaxle works the
same way as when in D (Drive).
However, when your vehicle cruises
at a constant speed for any length
of time, the transaxle shifts into a
fourth gear (Overdrive) and allows
the torque converter to lock-up.
Overdrive will increase your fuel
economy when you travel at cruising
speeds.
Overdrive may not be appropriate
for certain terrains. If the transaxle shifts back and forth between third
and fourth gears while you are driving on hilly roads, or if your vehicle
requires additional power for climbing hills, shift into D (Drive).
When to use D (Drive)
The D (Drive) position eliminates
the needless shifting back and forth
between third and fourth gears that
your vehicle may do when driving
on hilly terrain. It also gives more
engine braking than overdrive to
slow your vehicle on downgrades.
P R N D D 1
P R N D D 1
Driving
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