Dodge 2009 Durango - Manual (Page 299)

Torque Converter Clutch
A feature designed to improve fuel economy is included
in all automatic transmissions. A clutch within the torque
converter engages automatically at a calibrated speed at
light throttle. It engages at higher speeds under heavier
acceleration. This may result in a slightly different feeling
or response during normal operation in high gear. When
the vehicle speed drops below a calibrated speed, or
during acceleration, the clutch automatically and
smoothly disengages. The feature is operational in
OVERDRIVE and in DRIVE.
NOTE:
• The torque converter clutch will not engage until the
transmission fluid and engine coolant are warm (usu-
ally after 1-3 miles [1.6 - 4.8 km] of driving). Because
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmis-
sion is not shifting into Overdrive when cold. This is
normal. Pressing the TOW/HAUL button, when the
transmission is sufficiently warm, will demonstrate
that the transmission is able to shift into, and out of,
Overdrive. For vehicles with 4.7L or 5.7L engines
(which have two Overdrive gears), the transmission
may not shift into 5th gear until the transmission fluid
and engine coolant are warm.
• If the vehicle has not been driven in several days, the
first few seconds of operation after shifting the trans-
mission into gear may seem sluggish. This is due to the
fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
cause damage to the transmission. The torque con-
verter will refill within five seconds of shifting from
PARK into any other gear position.
STARTING AND OPERATING 297
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