RAM 2012 Truck Chassis cab Owner's Manual page 291

If the transmission operating temperature exceeds nor-
mal operating limits, the powertrain controller will
modify the transmission shift schedule and expand the
range of torque converter clutch engagement. This is
done to prevent transmission damage due to overheat-
ing.
If the transmission becomes extremely hot, the "Trans-
mission Temperature Warning Light" may illuminate and
the transmission may downshift out of Overdrive until
the transmission cools down.
NOTE: Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of both the
torque converter clutch and the top overdrive gear are
inhibited until the transmission fluid is warm (refer to the
"Note" under "Torque Converter Clutch" in this section).
During extremely cold temperatures (-16°F [-27°C] or
below), operation may briefly be limited to first and
direct gears only. Normal operation will resume once the
transmission temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear regardless of which forward gear is
selected. PARK, REVERSE, and NEUTRAL will continue
STARTING AND OPERATING 289
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