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CAunON: Do not change from "1-4" or "1-3" position to "1-2"
on icy or slippery roads while under way.
A forced downshift to 1st speed can be made while in
"1-2" position with vehicle speed less than 5 mph. Completely
depress accelerator pedal. Shift again to 2nd speed will auto-
matically be made when vehicle speed increases or pedal
is released.
Driving with Powermatic
Operating in "DRIVE" Range (Automatic Operation from
Converter through third, fourth, fifth and sixth gears).
The "Drive" Range is used for normal starting and operat-
ing and is most satisfactory for truck operation.
At engine
idle the truck remains standing. Upon opening the throttle, the
response is immediate. The transmission starts in converter
and continues progressively and automatically into lockup
and through the four gear ratios in this range. The driver de-
termines the rate of acceleration by the pressure he exerts
on the accelerator pedal. If at any time during the shift cycle,
the situation demands sudden acceleration or extra pulling
power, a rapid downshift is accomplished by pushing the ac-
celerator pedal through the "detent" resistance. The trans-
mission will remain in the higher ratio in this range only as
long as vehicle speed and load requires the higher ratio.
When operating at part throttle, the driver can overcontrol
the transmission at any time to obtain the best performance
or economy.
Operating in "INTERMEDIATE" Range (Automatic Opera-
tion from Converter through third and fourth gears).
The "Interme'diate" range is the performance range for
heavy pulling, congested traffic operation and descending long
grades. In operation, this range performs in the same manner
as Drive range in that the driver determines the rate of ac-
celeration, and he can downshift to the next highest gear
ratio by pushing the accelerator pedal through the "detent"
resistance. The transmission will remain in the higher ratios
within this range only as long as vehicle speed and load re-
quire the higher ratio. This is the recommended range for
using the Powermatic brake and driving in heavy traffic. The
brake rotor operates at the most effective rpm in this range
and allows efficient braking effort from both the Powermatic
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